21312004412 has 24 divisors (see below), whose sum is σ = 37580823504. Its totient is φ = 10574678912.

The previous prime is 21312004411. The next prime is 21312004433. The reversal of 21312004412 is 21440021312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21312004411) 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, 2536883 + ... + 2545269.

It is an arithmetic number, because the mean of its divisors is an integer number (1565867646).

Almost surely, 2^21312004412 is an apocalyptic number.

It is an amenable number.

21312004412 is a deficient number, since it is larger than the sum of its proper divisors (16268819092).

21312004412 is a wasteful number, since it uses less digits than its factorization.

21312004412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13165 (or 13163 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21312004412 its reverse (21440021312), we get a palindrome (42752025724).

The spelling of 21312004412 in words is "twenty-one billion, three hundred twelve million, four thousand, four hundred twelve".