21696187 has 8 divisors (see below), whose sum is σ = 22874112. Its totient is φ = 20548200.

The previous prime is 21696179. The next prime is 21696203. The reversal of 21696187 is 78169612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21696187 - 2³ = 21696179 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21696127) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5989 + ... + 8902.

It is an arithmetic number, because the mean of its divisors is an integer number (2859264).

Almost surely, 2^21696187 is an apocalyptic number.

21696187 is a deficient number, since it is larger than the sum of its proper divisors (1177925).

21696187 is a wasteful number, since it uses less digits than its factorization.

21696187 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14969.

The product of its digits is 36288, while the sum is 40.

The square root of 21696187 is about 4657.9165943585. The cubic root of 21696187 is about 278.9081072653.

The spelling of 21696187 in words is "twenty-one million, six hundred ninety-six thousand, one hundred eighty-seven".