20553131977 has 6 divisors (see below), whose sum is σ = 23908745418. Its totient is φ = 17616970224.

The previous prime is 20553131927. The next prime is 20553131993. The reversal of 20553131977 is 77913135502.

It can be written as a sum of positive squares in only one way, i.e., 17121984201 + 3431147776 = 130851^2 + 58576^2 .

It is a de Polignac number, because none of the positive numbers 2^k-20553131977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20553131917) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 209725788 + ... + 209725885.

It is an arithmetic number, because the mean of its divisors is an integer number (3984790903).

Almost surely, 2^20553131977 is an apocalyptic number.

It is an amenable number.

20553131977 is a deficient number, since it is larger than the sum of its proper divisors (3355613441).

20553131977 is an equidigital number, since it uses as much as digits as its factorization.

20553131977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 419451687 (or 419451680 counting only the distinct ones).

The product of its (nonzero) digits is 198450, while the sum is 43.

The spelling of 20553131977 in words is "twenty billion, five hundred fifty-three million, one hundred thirty-one thousand, nine hundred seventy-seven".