221442172961 has 2 divisors, whose sum is σ = 221442172962. Its totient is φ = 221442172960.

The previous prime is 221442172957. The next prime is 221442173003. The reversal of 221442172961 is 169271244122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 151725051361 + 69717121600 = 389519^2 + 264040^2 .

It is a cyclic number.

It is not a de Polignac number, because 221442172961 - 2² = 221442172957 is a prime.

It is not a weakly prime, because it can be changed into another prime (221442172951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110721086480 + 110721086481.

It is an arithmetic number, because the mean of its divisors is an integer number (110721086481).

Almost surely, 2^221442172961 is an apocalyptic number.

It is an amenable number.

221442172961 is a deficient number, since it is larger than the sum of its proper divisors (1).

221442172961 is an equidigital number, since it uses as much as digits as its factorization.

221442172961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 96768, while the sum is 41.

The spelling of 221442172961 in words is "two hundred twenty-one billion, four hundred forty-two million, one hundred seventy-two thousand, nine hundred sixty-one".