20557825557 has 16 divisors (see below), whose sum is σ = 27517372800. Its totient is φ = 13651852032.

The previous prime is 20557825543. The next prime is 20557825567. The reversal of 20557825557 is 75552875502.

It is not a de Polignac number, because 20557825557 - 2⁶ = 20557825493 is a prime.

It is a super-4 number, since 4×20557825557⁴ (a number of 42 digits) contains 4444 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20557825567) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 808713 + ... + 833745.

It is an arithmetic number, because the mean of its divisors is an integer number (1719835800).

Almost surely, 2^20557825557 is an apocalyptic number.

It is an amenable number.

20557825557 is a deficient number, since it is larger than the sum of its proper divisors (6959547243).

20557825557 is a wasteful number, since it uses less digits than its factorization.

20557825557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26092.

The product of its (nonzero) digits is 4900000, while the sum is 51.

The spelling of 20557825557 in words is "twenty billion, five hundred fifty-seven million, eight hundred twenty-five thousand, five hundred fifty-seven".