213121312 has 96 divisors (see below), whose sum is σ = 458970624. Its totient is φ = 97152000.

The previous prime is 213121303. The next prime is 213121313.

213121312 is nontrivially palindromic in base 10.

213121312 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is not an unprimeable number, because it can be changed into a prime (213121313) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2110062 + ... + 2110162.

It is an arithmetic number, because the mean of its divisors is an integer number (4780944).

Almost surely, 2^213121312 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 213121312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (229485312).

213121312 is an abundant number, since it is smaller than the sum of its proper divisors (245849312).

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

213121312 is a wasteful number, since it uses less digits than its factorization.

213121312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242 (or 234 counting only the distinct ones).

The product of its digits is 72, while the sum is 16.

The square root of 213121312 is about 14598.6750083698. The cubic root of 213121312 is about 597.3226186340.

The spelling of 213121312 in words is "two hundred thirteen million, one hundred twenty-one thousand, three hundred twelve".