20553131256 has 64 divisors (see below), whose sum is σ = 60748185600. Its totient is φ = 5669827968.

The previous prime is 20553131243. The next prime is 20553131267. The reversal of 20553131256 is 65213135502.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2104440 + ... + 2114183.

It is an arithmetic number, because the mean of its divisors is an integer number (949190400).

Almost surely, 2^20553131256 is an apocalyptic number.

It is an amenable number.

20553131256 is an abundant number, since it is smaller than the sum of its proper divisors (40195054344).

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

20553131256 is a wasteful number, since it uses less digits than its factorization.

20553131256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4218668 (or 4218664 counting only the distinct ones).

The product of its (nonzero) digits is 27000, while the sum is 33.

Adding to 20553131256 its reverse (65213135502), we get a palindrome (85766266758).

The spelling of 20553131256 in words is "twenty billion, five hundred fifty-three million, one hundred thirty-one thousand, two hundred fifty-six".