1321915716 has 144 divisors (see below), whose sum is σ = 3884811840. Its totient is φ = 374568960.

The previous prime is 1321915667. The next prime is 1321915723. The reversal of 1321915716 is 6175191231.

It is a happy number.

It is a super-2 number, since 2×1321915716² = 3494922320415585312, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1204480 + ... + 1205576.

It is an arithmetic number, because the mean of its divisors is an integer number (26977860).

Almost surely, 2^1321915716 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1321915716, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1942405920).

1321915716 is an abundant number, since it is smaller than the sum of its proper divisors (2562896124).

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

1321915716 is a wasteful number, since it uses less digits than its factorization.

1321915716 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1314 (or 1309 counting only the distinct ones).

The product of its digits is 11340, while the sum is 36.

The square root of 1321915716 is about 36358.1588642769. The cubic root of 1321915716 is about 1097.4917272879.

The spelling of 1321915716 in words is "one billion, three hundred twenty-one million, nine hundred fifteen thousand, seven hundred sixteen".