1297887921 has 32 divisors (see below), whose sum is σ = 2100080640. Its totient is φ = 785667600.

The previous prime is 1297887869. The next prime is 1297887949.

1297887921 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1297887921 - 2²⁵ = 1264333489 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1297880921) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 313656 + ... + 317766.

It is an arithmetic number, because the mean of its divisors is an integer number (65627520).

Almost surely, 2^1297887921 is an apocalyptic number.

1297887921 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1297887921 is a deficient number, since it is larger than the sum of its proper divisors (802192719).

1297887921 is a wasteful number, since it uses less digits than its factorization.

1297887921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5194 (or 5188 counting only the distinct ones).

The product of its digits is 1016064, while the sum is 54.

The square root of 1297887921 is about 36026.2115826796. The cubic root of 1297887921 is about 1090.8015093513.

The spelling of 1297887921 in words is "one billion, two hundred ninety-seven million, eight hundred eighty-seven thousand, nine hundred twenty-one".