21231613212 has 12 divisors (see below), whose sum is σ = 49540430856. Its totient is φ = 7077204400.

The previous prime is 21231613159. The next prime is 21231613331.

21231613212 is nontrivially palindromic in base 10.

It is a tau number, because it is divible by the number of its divisors (12).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 884650539 + ... + 884650562.

It is an arithmetic number, because the mean of its divisors is an integer number (4128369238).

Almost surely, 2^21231613212 is an apocalyptic number.

It is an amenable number.

21231613212 is an abundant number, since it is smaller than the sum of its proper divisors (28308817644).

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

21231613212 is a wasteful number, since it uses less digits than its factorization.

21231613212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1769301108 (or 1769301106 counting only the distinct ones).

The product of its digits is 864, while the sum is 24.

The spelling of 21231613212 in words is "twenty-one billion, two hundred thirty-one million, six hundred thirteen thousand, two hundred twelve".