77662922521 has 2 divisors, whose sum is σ = 77662922522. Its totient is φ = 77662922520.

The previous prime is 77662922473. The next prime is 77662922531. The reversal of 77662922521 is 12522926677.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63522145296 + 14140777225 = 252036^2 + 118915^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77662922521 is a prime.

It is not a weakly prime, because it can be changed into another prime (77662922531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38831461260 + 38831461261.

It is an arithmetic number, because the mean of its divisors is an integer number (38831461261).

Almost surely, 2^77662922521 is an apocalyptic number.

It is an amenable number.

77662922521 is a deficient number, since it is larger than the sum of its proper divisors (1).

77662922521 is an equidigital number, since it uses as much as digits as its factorization.

77662922521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1270080, while the sum is 49.

The spelling of 77662922521 in words is "seventy-seven billion, six hundred sixty-two million, nine hundred twenty-two thousand, five hundred twenty-one".