213120021231 has 48 divisors (see below), whose sum is σ = 335760568416. Its totient is φ = 129482293248.

The previous prime is 213120021223. The next prime is 213120021271. The reversal of 213120021231 is 132120021312.

213120021231 is a `hidden beast` number, since 213 + 1 + 200 + 21 + 231 = 666.

It is not a de Polignac number, because 213120021231 - 2³ = 213120021223 is a prime.

It is a super-2 number, since 2×213120021231² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213120021271) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3366436 + ... + 3429158.

It is an arithmetic number, because the mean of its divisors is an integer number (6995011842).

Almost surely, 2^213120021231 is an apocalyptic number.

213120021231 is a deficient number, since it is larger than the sum of its proper divisors (122640547185).

213120021231 is a wasteful number, since it uses less digits than its factorization.

213120021231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63112 (or 63109 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 213120021231 its reverse (132120021312), we get a palindrome (345240042543).

The spelling of 213120021231 in words is "two hundred thirteen billion, one hundred twenty million, twenty-one thousand, two hundred thirty-one".