1291256416 has 24 divisors (see below), whose sum is σ = 2675960280. Its totient is φ = 611647488.

The previous prime is 1291256347. The next prime is 1291256441. The reversal of 1291256416 is 6146521921.

It is a super-2 number, since 2×1291256416² = 3334686263722330112, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1061281 + ... + 1062496.

It is an arithmetic number, because the mean of its divisors is an integer number (111498345).

Almost surely, 2^1291256416 is an apocalyptic number.

1291256416 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1291256416 is an abundant number, since it is smaller than the sum of its proper divisors (1384703864).

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

1291256416 is a wasteful number, since it uses less digits than its factorization.

1291256416 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2123806 (or 2123798 counting only the distinct ones).

The product of its digits is 25920, while the sum is 37.

The square root of 1291256416 is about 35934.0564924140. The cubic root of 1291256416 is about 1088.9405343885.

The spelling of 1291256416 in words is "one billion, two hundred ninety-one million, two hundred fifty-six thousand, four hundred sixteen".