21213617232 has 80 divisors (see below), whose sum is σ = 57380577408. Its totient is φ = 6740574720.

The previous prime is 21213617219. The next prime is 21213617239. The reversal of 21213617232 is 23271631212.

It is a self number, because there is not a number n which added to its sum of digits gives 21213617232.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21213617239) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 290682 + ... + 356262.

Almost surely, 2^21213617232 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21213617232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28690288704).

21213617232 is an abundant number, since it is smaller than the sum of its proper divisors (36166960176).

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

21213617232 is a wasteful number, since it uses less digits than its factorization.

21213617232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65908 (or 65902 counting only the distinct ones).

The product of its digits is 6048, while the sum is 30.

The spelling of 21213617232 in words is "twenty-one billion, two hundred thirteen million, six hundred seventeen thousand, two hundred thirty-two".