20507031977 has 2 divisors, whose sum is σ = 20507031978. Its totient is φ = 20507031976.

The previous prime is 20507031907. The next prime is 20507031989. The reversal of 20507031977 is 77913070502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12118487056 + 8388544921 = 110084^2 + 91589^2 .

It is a cyclic number.

It is not a de Polignac number, because 20507031977 - 2³⁰ = 19433290153 is a prime.

It is not a weakly prime, because it can be changed into another prime (20507031907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10253515988 + 10253515989.

It is an arithmetic number, because the mean of its divisors is an integer number (10253515989).

Almost surely, 2^20507031977 is an apocalyptic number.

It is an amenable number.

20507031977 is a deficient number, since it is larger than the sum of its proper divisors (1).

20507031977 is an equidigital number, since it uses as much as digits as its factorization.

20507031977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 92610, while the sum is 41.

The spelling of 20507031977 in words is "twenty billion, five hundred seven million, thirty-one thousand, nine hundred seventy-seven".