3121321200 has 120 divisors (see below), whose sum is σ = 10162782576. Its totient is φ = 818688000.

The previous prime is 3121321153. The next prime is 3121321213. The reversal of 3121321200 is 21231213.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 3121321200.

It is a congruent number.

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, 51880 + ... + 94520.

Almost surely, 2^3121321200 is an apocalyptic number.

3121321200 is a gapful number since it is divisible by the number (30) 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 3121321200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5081391288).

3121321200 is an abundant number, since it is smaller than the sum of its proper divisors (7041461376).

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

3121321200 is a wasteful number, since it uses less digits than its factorization.

3121321200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42723 (or 42712 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 3121321200 is about 55868.7855604541. The cubic root of 3121321200 is about 1461.4349437585.

Adding to 3121321200 its reverse (21231213), we get a palindrome (3142552413).

The spelling of 3121321200 in words is "three billion, one hundred twenty-one million, three hundred twenty-one thousand, two hundred".