21212320232 has 16 divisors (see below), whose sum is σ = 39775544100. Its totient is φ = 10605508480.

The previous prime is 21212320169. The next prime is 21212320243. The reversal of 21212320232 is 23202321212.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 20864646916 + 347673316 = 144446^2 + 18646^2 .

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, 74444 + ... + 219012.

Almost surely, 2^21212320232 is an apocalyptic number.

It is an amenable number.

21212320232 is a deficient number, since it is larger than the sum of its proper divisors (18563223868).

21212320232 is a wasteful number, since it uses less digits than its factorization.

21212320232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162916 (or 162912 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 21212320232 its reverse (23202321212), we get a palindrome (44414641444).

The spelling of 21212320232 in words is "twenty-one billion, two hundred twelve million, three hundred twenty thousand, two hundred thirty-two".