20993656320 has 1920 divisors, whose sum is σ = 102953410560. Its totient is φ = 3822059520.

The previous prime is 20993656291. The next prime is 20993656349. The reversal of 20993656320 is 2365639902.

20993656320 is a `hidden beast` number, since 2 + 0 + 9 + 9 + 3 + 6 + 5 + 632 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (20993656291) and next prime (20993656349).

It is a tau number, because it is divible by the number of its divisors (1920).

It is a super-4 number, since 4×20993656320⁴ (a number of 42 digits) contains 4444 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 677214705 + ... + 677214735.

It is an arithmetic number, because the mean of its divisors is an integer number (53621568).

Almost surely, 2^20993656320 is an apocalyptic number.

20993656320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20993656320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51476705280).

20993656320 is an abundant number, since it is smaller than the sum of its proper divisors (81959754240).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20993656320 is a wasteful number, since it uses less digits than its factorization.

20993656320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116 (or 97 counting only the distinct ones).

The product of its (nonzero) digits is 524880, while the sum is 45.

It can be divided in two parts, 209936 and 56320, that added together give a square (266256 = 516²).

The spelling of 20993656320 in words is "twenty billion, nine hundred ninety-three million, six hundred fifty-six thousand, three hundred twenty".