21322220977 has 2 divisors, whose sum is σ = 21322220978. Its totient is φ = 21322220976.

The previous prime is 21322220923. The next prime is 21322221017. The reversal of 21322220977 is 77902222312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16919765776 + 4402455201 = 130076^2 + 66351^2 .

It is a cyclic number.

It is not a de Polignac number, because 21322220977 - 2¹⁹ = 21321696689 is a prime.

It is not a weakly prime, because it can be changed into another prime (21322220677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10661110488 + 10661110489.

It is an arithmetic number, because the mean of its divisors is an integer number (10661110489).

Almost surely, 2^21322220977 is an apocalyptic number.

It is an amenable number.

21322220977 is a deficient number, since it is larger than the sum of its proper divisors (1).

21322220977 is an equidigital number, since it uses as much as digits as its factorization.

21322220977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 42336, while the sum is 37.

The spelling of 21322220977 in words is "twenty-one billion, three hundred twenty-two million, two hundred twenty thousand, nine hundred seventy-seven".