21213400432 has 80 divisors (see below), whose sum is σ = 47498959872. Its totient is φ = 8989839360.

The previous prime is 21213400393. The next prime is 21213400441. The reversal of 21213400432 is 23400431212.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14038557 + ... + 14040067.

Almost surely, 2^21213400432 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 21213400432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23749479936).

21213400432 is an abundant number, since it is smaller than the sum of its proper divisors (26285559440).

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

21213400432 is a wasteful number, since it uses less digits than its factorization.

21213400432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2846 (or 2840 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 22.

Adding to 21213400432 its reverse (23400431212), we get a palindrome (44613831644).

The spelling of 21213400432 in words is "twenty-one billion, two hundred thirteen million, four hundred thousand, four hundred thirty-two".