20618836560 has 240 divisors, whose sum is σ = 81690485760. Its totient is φ = 4560814080.

The previous prime is 20618836523. The next prime is 20618836577. The reversal of 20618836560 is 6563881602.

20618836560 is a `hidden beast` number, since 2 + 0 + 6 + 1 + 8 + 83 + 6 + 560 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

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 polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 90256 + ... + 222224.

It is an arithmetic number, because the mean of its divisors is an integer number (340377024).

Almost surely, 2^20618836560 is an apocalyptic number.

20618836560 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 20618836560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40845242880).

20618836560 is an abundant number, since it is smaller than the sum of its proper divisors (61071649200).

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

20618836560 is a wasteful number, since it uses less digits than its factorization.

20618836560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132026 (or 132017 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 45.

The spelling of 20618836560 in words is "twenty billion, six hundred eighteen million, eight hundred thirty-six thousand, five hundred sixty".