21321220332 has 24 divisors (see below), whose sum is σ = 49785577072. Its totient is φ = 7101921600.

The previous prime is 21321220313. The next prime is 21321220337. The reversal of 21321220332 is 23302212312.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21321220299 and 21321220308.

It is not an unprimeable number, because it can be changed into a prime (21321220337) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 626719 + ... + 659862.

Almost surely, 2^21321220332 is an apocalyptic number.

It is an amenable number.

21321220332 is an abundant number, since it is smaller than the sum of its proper divisors (28464356740).

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

21321220332 is a wasteful number, since it uses less digits than its factorization.

21321220332 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1287969 (or 1287967 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 21.

Adding to 21321220332 its reverse (23302212312), we get a palindrome (44623432644).

The spelling of 21321220332 in words is "twenty-one billion, three hundred twenty-one million, two hundred twenty thousand, three hundred thirty-two".