20568097557 has 64 divisors (see below), whose sum is σ = 36138240000. Its totient is φ = 11553684912.

The previous prime is 20568097549. The next prime is 20568097591. The reversal of 20568097557 is 75579086502.

20568097557 is a `hidden beast` number, since 2 + 0 + 5 + 6 + 80 + 9 + 7 + 557 = 666.

It is not a de Polignac number, because 20568097557 - 2³ = 20568097549 is a prime.

It is a super-2 number, since 2×20568097557² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20568097157) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 527578 + ... + 565220.

It is an arithmetic number, because the mean of its divisors is an integer number (564660000).

Almost surely, 2^20568097557 is an apocalyptic number.

20568097557 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

20568097557 is a deficient number, since it is larger than the sum of its proper divisors (15570142443).

20568097557 is an equidigital number, since it uses as much as digits as its factorization.

20568097557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37732 (or 37712 counting only the distinct ones).

The product of its (nonzero) digits is 5292000, while the sum is 54.

The spelling of 20568097557 in words is "twenty billion, five hundred sixty-eight million, ninety-seven thousand, five hundred fifty-seven".