1291937664 has 32 divisors (see below), whose sum is σ = 3431710440. Its totient is φ = 430645760.

The previous prime is 1291937659. The next prime is 1291937677. The reversal of 1291937664 is 4667391921.

It is a tau number, because it is divible by the number of its divisors (32).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1681827 + ... + 1682594.

Almost surely, 2^1291937664 is an apocalyptic number.

It is an amenable number.

1291937664 is an abundant number, since it is smaller than the sum of its proper divisors (2139772776).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1291937664 is an equidigital number, since it uses as much as digits as its factorization.

1291937664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3364438 (or 3364426 counting only the distinct ones).

The product of its digits is 489888, while the sum is 48.

The square root of 1291937664 is about 35943.5343838082. The cubic root of 1291937664 is about 1089.1320037536.

The spelling of 1291937664 in words is "one billion, two hundred ninety-one million, nine hundred thirty-seven thousand, six hundred sixty-four".