1397901961 has 2 divisors, whose sum is σ = 1397901962. Its totient is φ = 1397901960.

The previous prime is 1397901881. The next prime is 1397901971. The reversal of 1397901961 is 1691097931.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1073217600 + 324684361 = 32760^2 + 18019^2 .

It is a cyclic number.

It is not a de Polignac number, because 1397901961 - 2²⁹ = 861031049 is a prime.

It is not a weakly prime, because it can be changed into another prime (1397901971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 698950980 + 698950981.

It is an arithmetic number, because the mean of its divisors is an integer number (698950981).

Almost surely, 2^1397901961 is an apocalyptic number.

It is an amenable number.

1397901961 is a deficient number, since it is larger than the sum of its proper divisors (1).

1397901961 is an equidigital number, since it uses as much as digits as its factorization.

1397901961 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 91854, while the sum is 46.

The square root of 1397901961 is about 37388.5271306587. The cubic root of 1397901961 is about 1118.1298405488.

The spelling of 1397901961 in words is "one billion, three hundred ninety-seven million, nine hundred one thousand, nine hundred sixty-one".