1357664981 has 4 divisors (see below), whose sum is σ = 1363646112. Its totient is φ = 1351683852.

The previous prime is 1357664977. The next prime is 1357664993. The reversal of 1357664981 is 1894667531.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1357664981 - 2² = 1357664977 is a prime.

It is a super-2 number, since 2×1357664981² = 3686508401267460722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1357664681) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2990225 + ... + 2990678.

It is an arithmetic number, because the mean of its divisors is an integer number (340911528).

Almost surely, 2^1357664981 is an apocalyptic number.

It is an amenable number.

1357664981 is a deficient number, since it is larger than the sum of its proper divisors (5981131).

1357664981 is an equidigital number, since it uses as much as digits as its factorization.

1357664981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5981130.

The product of its digits is 1088640, while the sum is 50.

The square root of 1357664981 is about 36846.5056823575. The cubic root of 1357664981 is about 1107.2972093272.

The spelling of 1357664981 in words is "one billion, three hundred fifty-seven million, six hundred sixty-four thousand, nine hundred eighty-one".