21228470924 has 6 divisors (see below), whose sum is σ = 37149824124. Its totient is φ = 10614235460.

The previous prime is 21228470881. The next prime is 21228470927. The reversal of 21228470924 is 42907482212.

It is a super-2 number, since 2×21228470924² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21228470927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2653558862 + ... + 2653558869.

It is an arithmetic number, because the mean of its divisors is an integer number (6191637354).

Almost surely, 2^21228470924 is an apocalyptic number.

It is an amenable number.

21228470924 is a deficient number, since it is larger than the sum of its proper divisors (15921353200).

21228470924 is a wasteful number, since it uses less digits than its factorization.

21228470924 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5307117735 (or 5307117733 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 41.

The spelling of 21228470924 in words is "twenty-one billion, two hundred twenty-eight million, four hundred seventy thousand, nine hundred twenty-four".