21612079605 has 64 divisors (see below), whose sum is σ = 36825772032. Its totient is φ = 10800345600.

The previous prime is 21612079589. The next prime is 21612079609. The reversal of 21612079605 is 50697021612.

It is not a de Polignac number, because 21612079605 - 2⁴ = 21612079589 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21612079609) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3800094 + ... + 3805776.

It is an arithmetic number, because the mean of its divisors is an integer number (575402688).

Almost surely, 2^21612079605 is an apocalyptic number.

It is an amenable number.

21612079605 is a deficient number, since it is larger than the sum of its proper divisors (15213692427).

21612079605 is a wasteful number, since it uses less digits than its factorization.

21612079605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5938.

The product of its (nonzero) digits is 45360, while the sum is 39.

The spelling of 21612079605 in words is "twenty-one billion, six hundred twelve million, seventy-nine thousand, six hundred five".