21213343432 has 16 divisors (see below), whose sum is σ = 39780976140. Its totient is φ = 10605083136.

The previous prime is 21213343367. The next prime is 21213343447. The reversal of 21213343432 is 23434331212.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 21092914756 + 120428676 = 145234^2 + 10974^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21213343432.

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, 140833 + ... + 249520.

Almost surely, 2^21213343432 is an apocalyptic number.

It is an amenable number.

21213343432 is a deficient number, since it is larger than the sum of its proper divisors (18567632708).

21213343432 is a wasteful number, since it uses less digits than its factorization.

21213343432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 397152 (or 397148 counting only the distinct ones).

The product of its digits is 10368, while the sum is 28.

Adding to 21213343432 its reverse (23434331212), we get a palindrome (44647674644).

The spelling of 21213343432 in words is "twenty-one billion, two hundred thirteen million, three hundred forty-three thousand, four hundred thirty-two".