20941653977 has 2 divisors, whose sum is σ = 20941653978. Its totient is φ = 20941653976.

The previous prime is 20941653917. The next prime is 20941653989. The reversal of 20941653977 is 77935614902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20569009561 + 372644416 = 143419^2 + 19304^2 .

It is a cyclic number.

It is not a de Polignac number, because 20941653977 - 2²⁸ = 20673218521 is a prime.

It is not a weakly prime, because it can be changed into another prime (20941653917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10470826988 + 10470826989.

It is an arithmetic number, because the mean of its divisors is an integer number (10470826989).

Almost surely, 2^20941653977 is an apocalyptic number.

It is an amenable number.

20941653977 is a deficient number, since it is larger than the sum of its proper divisors (1).

20941653977 is an equidigital number, since it uses as much as digits as its factorization.

20941653977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2857680, while the sum is 53.

The spelling of 20941653977 in words is "twenty billion, nine hundred forty-one million, six hundred fifty-three thousand, nine hundred seventy-seven".