21231013212 has 72 divisors (see below), whose sum is σ = 56512856400. Its totient is φ = 6702041088.

The previous prime is 21231013211. The next prime is 21231013229.

21231013212 is a `hidden beast` number, since 212 + 310 + 132 + 12 = 666.

21231013212 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21231013211) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2930058 + ... + 2937294.

Almost surely, 2^21231013212 is an apocalyptic number.

It is an amenable number.

21231013212 is an abundant number, since it is smaller than the sum of its proper divisors (35281843188).

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

21231013212 is a wasteful number, since it uses less digits than its factorization.

21231013212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11555 (or 11550 counting only the distinct ones).

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

It can be divided in two parts, 212310 and 13212, that added together give a palindrome (225522).

The spelling of 21231013212 in words is "twenty-one billion, two hundred thirty-one million, thirteen thousand, two hundred twelve".