213121123210 has 16 divisors (see below), whose sum is σ = 384472413000. Its totient is φ = 85058584576.

The previous prime is 213121123153. The next prime is 213121123289. The reversal of 213121123210 is 12321121312.

It can be written as a sum of positive squares in 4 ways, for example, as 151318666009 + 61802457201 = 388997^2 + 248601^2 .

It is a super-2 number, since 2×213121123210² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23728375 + ... + 23737354.

Almost surely, 2^213121123210 is an apocalyptic number.

213121123210 is a deficient number, since it is larger than the sum of its proper divisors (171351289790).

213121123210 is a wasteful number, since it uses less digits than its factorization.

213121123210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47466185.

The product of its (nonzero) digits is 144, while the sum is 19.

Adding to 213121123210 its reverse (12321121312), we get a palindrome (225442244522).

The spelling of 213121123210 in words is "two hundred thirteen billion, one hundred twenty-one million, one hundred twenty-three thousand, two hundred ten".