1397271331 has 2 divisors, whose sum is σ = 1397271332. Its totient is φ = 1397271330.

The previous prime is 1397271313. The next prime is 1397271353. The reversal of 1397271331 is 1331727931.

Together with previous prime (1397271313) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1397271331 - 2⁵ = 1397271299 is a prime.

It is a super-2 number, since 2×1397271331² = 3904734344869023122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1397271391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 698635665 + 698635666.

It is an arithmetic number, because the mean of its divisors is an integer number (698635666).

Almost surely, 2^1397271331 is an apocalyptic number.

1397271331 is the 19981-st centered heptagonal number.

1397271331 is a deficient number, since it is larger than the sum of its proper divisors (1).

1397271331 is an equidigital number, since it uses as much as digits as its factorization.

1397271331 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23814, while the sum is 37.

The square root of 1397271331 is about 37380.0927098904. The cubic root of 1397271331 is about 1117.9616760896.

The spelling of 1397271331 in words is "one billion, three hundred ninety-seven million, two hundred seventy-one thousand, three hundred thirty-one".