21224013404 has 24 divisors (see below), whose sum is σ = 40700287488. Its totient is φ = 9604013040.

The previous prime is 21224013397. The next prime is 21224013413. The reversal of 21224013404 is 40431042212.

It is a self number, because there is not a number n which added to its sum of digits gives 21224013404.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1071722 + ... + 1091345.

It is an arithmetic number, because the mean of its divisors is an integer number (1695845312).

Almost surely, 2^21224013404 is an apocalyptic number.

It is an amenable number.

21224013404 is a deficient number, since it is larger than the sum of its proper divisors (19476274084).

21224013404 is a wasteful number, since it uses less digits than its factorization.

21224013404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2163305 (or 2163303 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 23.

Adding to 21224013404 its reverse (40431042212), we get a palindrome (61655055616).

The spelling of 21224013404 in words is "twenty-one billion, two hundred twenty-four million, thirteen thousand, four hundred four".