21770757937 has 2 divisors, whose sum is σ = 21770757938. Its totient is φ = 21770757936.

The previous prime is 21770757919. The next prime is 21770758001. The reversal of 21770757937 is 73975707712.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18225270001 + 3545487936 = 135001^2 + 59544^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21770757937 is a prime.

It is not a weakly prime, because it can be changed into another prime (21770757917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10885378968 + 10885378969.

It is an arithmetic number, because the mean of its divisors is an integer number (10885378969).

Almost surely, 2^21770757937 is an apocalyptic number.

It is an amenable number.

21770757937 is a deficient number, since it is larger than the sum of its proper divisors (1).

21770757937 is an equidigital number, since it uses as much as digits as its factorization.

21770757937 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4537890, while the sum is 55.

The spelling of 21770757937 in words is "twenty-one billion, seven hundred seventy million, seven hundred fifty-seven thousand, nine hundred thirty-seven".