20404557756 has 72 divisors (see below), whose sum is σ = 56288179584. Its totient is φ = 6180884640.

The previous prime is 20404557749. The next prime is 20404557763. The reversal of 20404557756 is 65775540402.

20404557756 is a `hidden beast` number, since 2 + 0 + 40 + 4 + 557 + 7 + 56 = 666.

It is an interprime number because it is at equal distance from previous prime (20404557749) and next prime (20404557763).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1260345 + ... + 1276431.

It is an arithmetic number, because the mean of its divisors is an integer number (781780272).

Almost surely, 2^20404557756 is an apocalyptic number.

It is an amenable number.

20404557756 is an abundant number, since it is smaller than the sum of its proper divisors (35883621828).

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

20404557756 is a wasteful number, since it uses less digits than its factorization.

20404557756 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19311 (or 19306 counting only the distinct ones).

The product of its (nonzero) digits is 1176000, while the sum is 45.

The spelling of 20404557756 in words is "twenty billion, four hundred four million, five hundred fifty-seven thousand, seven hundred fifty-six".