213121021110 has 16 divisors (see below), whose sum is σ = 511490450736. Its totient is φ = 56832272288.

The previous prime is 213121021097. The next prime is 213121021111. The reversal of 213121021110 is 11120121312.

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

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 213121021110.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213121021111) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3552016989 + ... + 3552017048.

It is an arithmetic number, because the mean of its divisors is an integer number (31968153171).

Almost surely, 2^213121021110 is an apocalyptic number.

213121021110 is an abundant number, since it is smaller than the sum of its proper divisors (298369429626).

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

213121021110 is a wasteful number, since it uses less digits than its factorization.

213121021110 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7104034047.

The product of its (nonzero) digits is 24, while the sum is 15.

Adding to 213121021110 its reverse (11120121312), we get a palindrome (224241142422).

The spelling of 213121021110 in words is "two hundred thirteen billion, one hundred twenty-one million, twenty-one thousand, one hundred ten".