16620565554 has 16 divisors (see below), whose sum is σ = 36934590240. Its totient is φ = 5540188500.

The previous prime is 16620565543. The next prime is 16620565573. The reversal of 16620565554 is 45556502661.

16620565554 is a `hidden beast` number, since 1 + 66 + 20 + 565 + 5 + 5 + 4 = 666.

It is a super-2 number, since 2×16620565554² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 153894072 + ... + 153894179.

It is an arithmetic number, because the mean of its divisors is an integer number (2308411890).

Almost surely, 2^16620565554 is an apocalyptic number.

16620565554 is an abundant number, since it is smaller than the sum of its proper divisors (20314024686).

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

16620565554 is a wasteful number, since it uses less digits than its factorization.

16620565554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 307788262 (or 307788256 counting only the distinct ones).

The product of its (nonzero) digits is 1080000, while the sum is 45.

The spelling of 16620565554 in words is "sixteen billion, six hundred twenty million, five hundred sixty-five thousand, five hundred fifty-four".