21486577617 has 32 divisors (see below), whose sum is σ = 32871787520. Its totient is φ = 13856832000.

The previous prime is 21486577613. The next prime is 21486577639. The reversal of 21486577617 is 71677568412.

21486577617 is a `hidden beast` number, since 2 + 1 + 4 + 8 + 6 + 577 + 61 + 7 = 666.

It is not a de Polignac number, because 21486577617 - 2² = 21486577613 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21486577613) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4066017 + ... + 4071297.

It is an arithmetic number, because the mean of its divisors is an integer number (1027243360).

Almost surely, 2^21486577617 is an apocalyptic number.

21486577617 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

21486577617 is a deficient number, since it is larger than the sum of its proper divisors (11385209903).

21486577617 is a wasteful number, since it uses less digits than its factorization.

21486577617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10182 (or 10176 counting only the distinct ones).

The product of its digits is 3951360, while the sum is 54.

The spelling of 21486577617 in words is "twenty-one billion, four hundred eighty-six million, five hundred seventy-seven thousand, six hundred seventeen".