221222220977 has 2 divisors, whose sum is σ = 221222220978. Its totient is φ = 221222220976.

The previous prime is 221222220917. The next prime is 221222221027. The reversal of 221222220977 is 779022222122.

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., 202658430976 + 18563790001 = 450176^2 + 136249^2 .

It is a cyclic number.

It is not a de Polignac number, because 221222220977 - 2¹² = 221222216881 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 221222220977.

It is not a weakly prime, because it can be changed into another prime (221222220917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110611110488 + 110611110489.

It is an arithmetic number, because the mean of its divisors is an integer number (110611110489).

Almost surely, 2^221222220977 is an apocalyptic number.

It is an amenable number.

221222220977 is a deficient number, since it is larger than the sum of its proper divisors (1).

221222220977 is an equidigital number, since it uses as much as digits as its factorization.

221222220977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 56448, while the sum is 38.

The spelling of 221222220977 in words is "two hundred twenty-one billion, two hundred twenty-two million, two hundred twenty thousand, nine hundred seventy-seven".