1291531456 has 14 divisors (see below), whose sum is σ = 2562882860. Its totient is φ = 645765696.

The previous prime is 1291531399. The next prime is 1291531459. The reversal of 1291531456 is 6541351921.

It is not an unprimeable number, because it can be changed into a prime (1291531459) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10090026 + ... + 10090153.

Almost surely, 2^1291531456 is an apocalyptic number.

1291531456 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1291531456 is a deficient number, since it is larger than the sum of its proper divisors (1271351404).

1291531456 is an equidigital number, since it uses as much as digits as its factorization.

1291531456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20180191 (or 20180181 counting only the distinct ones).

The product of its digits is 32400, while the sum is 37.

The square root of 1291531456 is about 35937.8832988255. The cubic root of 1291531456 is about 1089.0178443476.

The spelling of 1291531456 in words is "one billion, two hundred ninety-one million, five hundred thirty-one thousand, four hundred fifty-six".