21662088909 has 16 divisors (see below), whose sum is σ = 29324865024. Its totient is φ = 14221473200.

The previous prime is 21662088901. The next prime is 21662088937. The reversal of 21662088909 is 90988026612.

It is a cyclic number.

It is not a de Polignac number, because 21662088909 - 2³ = 21662088901 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21662088901) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 62427 + ... + 217304.

It is an arithmetic number, because the mean of its divisors is an integer number (1832804064).

Almost surely, 2^21662088909 is an apocalyptic number.

It is an amenable number.

21662088909 is a deficient number, since it is larger than the sum of its proper divisors (7662776115).

21662088909 is a wasteful number, since it uses less digits than its factorization.

21662088909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 280128.

The product of its (nonzero) digits is 746496, while the sum is 51.

The spelling of 21662088909 in words is "twenty-one billion, six hundred sixty-two million, eighty-eight thousand, nine hundred nine".