20738156544 has 288 divisors, whose sum is σ = 70999306560. Its totient is φ = 5924192256.

The previous prime is 20738156497. The next prime is 20738156557. The reversal of 20738156544 is 44565183702.

20738156544 is a `hidden beast` number, since 2 + 0 + 7 + 3 + 81 + 565 + 4 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a super-2 number, since 2×20738156544² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20738156544.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3480672 + ... + 3486624.

It is an arithmetic number, because the mean of its divisors is an integer number (246525370).

Almost surely, 2^20738156544 is an apocalyptic number.

20738156544 is a gapful number since it is divisible by the number (24) 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 20738156544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35499653280).

20738156544 is an abundant number, since it is smaller than the sum of its proper divisors (50261150016).

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

20738156544 is an frugal number, since it uses more digits than its factorization.

20738156544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5997 (or 5965 counting only the distinct ones).

The product of its (nonzero) digits is 806400, while the sum is 45.

The spelling of 20738156544 in words is "twenty billion, seven hundred thirty-eight million, one hundred fifty-six thousand, five hundred forty-four".