1321807872 has 312 divisors, whose sum is σ = 4462194688. Its totient is φ = 340623360.

The previous prime is 1321807847. The next prime is 1321807891. The reversal of 1321807872 is 2787081231.

It is a self number, because there is not a number n which added to its sum of digits gives 1321807872.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10407873 + ... + 10407999.

Almost surely, 2^1321807872 is an apocalyptic number.

1321807872 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1321807872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2231097344).

1321807872 is an abundant number, since it is smaller than the sum of its proper divisors (3140386816).

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

1321807872 is a wasteful number, since it uses less digits than its factorization.

1321807872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 183 (or 150 counting only the distinct ones).

The product of its (nonzero) digits is 37632, while the sum is 39.

The square root of 1321807872 is about 36356.6757556298. The cubic root of 1321807872 is about 1097.4618814323.

The spelling of 1321807872 in words is "one billion, three hundred twenty-one million, eight hundred seven thousand, eight hundred seventy-two".