213121021200 has 120 divisors (see below), whose sum is σ = 701149105728. Its totient is φ = 55296253440.

The previous prime is 213121021189. The next prime is 213121021247. The reversal of 213121021200 is 2120121312.

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 213121021200.

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, 2355612 + ... + 2444411.

Almost surely, 2^213121021200 is an apocalyptic number.

213121021200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

213121021200 is an abundant number, since it is smaller than the sum of its proper divisors (488028084528).

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

213121021200 is a wasteful number, since it uses less digits than its factorization.

213121021200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4800081 (or 4800070 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 213121021200 its reverse (2120121312), we get a palindrome (215241142512).

The spelling of 213121021200 in words is "two hundred thirteen billion, one hundred twenty-one million, twenty-one thousand, two hundred".