1297999631 has 2 divisors, whose sum is σ = 1297999632. Its totient is φ = 1297999630.

The previous prime is 1297999601. The next prime is 1297999673. The reversal of 1297999631 is 1369997921.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1297999631 - 2¹⁰ = 1297998607 is a prime.

It is a super-2 number, since 2×1297999631² = 3369606084152272322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1297999601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 648999815 + 648999816.

It is an arithmetic number, because the mean of its divisors is an integer number (648999816).

Almost surely, 2^1297999631 is an apocalyptic number.

1297999631 is a deficient number, since it is larger than the sum of its proper divisors (1).

1297999631 is an equidigital number, since it uses as much as digits as its factorization.

1297999631 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1653372, while the sum is 56.

The square root of 1297999631 is about 36027.7619482532. The cubic root of 1297999631 is about 1090.8328037691.

The spelling of 1297999631 in words is "one billion, two hundred ninety-seven million, nine hundred ninety-nine thousand, six hundred thirty-one".