20661055236 has 30 divisors (see below), whose sum is σ = 54012080430. Its totient is φ = 6887018304.

The previous prime is 20661055229. The next prime is 20661055277. The reversal of 20661055236 is 63255016602.

It is a happy number.

20661055236 is a `hidden beast` number, since 2 + 0 + 6 + 610 + 5 + 5 + 2 + 36 = 666.

It can be written as a sum of positive squares in only one way, i.e., 20658312900 + 2742336 = 143730^2 + 1656^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 20661055236.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 31884021 + ... + 31884668.

It is an arithmetic number, because the mean of its divisors is an integer number (1800402681).

Almost surely, 2^20661055236 is an apocalyptic number.

It is an amenable number.

20661055236 is an abundant number, since it is smaller than the sum of its proper divisors (33351025194).

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

20661055236 is a wasteful number, since it uses less digits than its factorization.

20661055236 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63768705 (or 63768694 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 36.

The spelling of 20661055236 in words is "twenty billion, six hundred sixty-one million, fifty-five thousand, two hundred thirty-six".