21639516489 has 48 divisors (see below), whose sum is σ = 34578545664. Its totient is φ = 12992918400.

The previous prime is 21639516487. The next prime is 21639516491. The reversal of 21639516489 is 98461593612.

21639516489 is a `hidden beast` number, since 2 + 1 + 63 + 95 + 16 + 489 = 666.

It is an interprime number because it is at equal distance from previous prime (21639516487) and next prime (21639516491).

It is not a de Polignac number, because 21639516489 - 2¹ = 21639516487 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21639516487) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 191859 + ... + 282999.

It is an arithmetic number, because the mean of its divisors is an integer number (720386368).

Almost surely, 2^21639516489 is an apocalyptic number.

It is an amenable number.

21639516489 is a deficient number, since it is larger than the sum of its proper divisors (12939029175).

21639516489 is a wasteful number, since it uses less digits than its factorization.

21639516489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91238 (or 91235 counting only the distinct ones).

The product of its digits is 2799360, while the sum is 54.

The spelling of 21639516489 in words is "twenty-one billion, six hundred thirty-nine million, five hundred sixteen thousand, four hundred eighty-nine".