21479204690 has 16 divisors (see below), whose sum is σ = 38666744280. Its totient is φ = 8590753920.

The previous prime is 21479204687. The next prime is 21479204707. The reversal of 21479204690 is 9640297412.

It can be written as a sum of positive squares in 4 ways, for example, as 8414943289 + 13064261401 = 91733^2 + 114299^2 .

It is a super-2 number, since 2×21479204690² (a number of 21 digits) contains 22 as substring.

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, 14555 + ... + 207774.

Almost surely, 2^21479204690 is an apocalyptic number.

21479204690 is a deficient number, since it is larger than the sum of its proper divisors (17187539590).

21479204690 is a wasteful number, since it uses less digits than its factorization.

21479204690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231997.

The product of its (nonzero) digits is 217728, while the sum is 44.

The spelling of 21479204690 in words is "twenty-one billion, four hundred seventy-nine million, two hundred four thousand, six hundred ninety".