21689196 has 24 divisors (see below), whose sum is σ = 50878464. Its totient is φ = 7191120.

The previous prime is 21689179. The next prime is 21689197. The reversal of 21689196 is 69198612.

It is not an unprimeable number, because it can be changed into a prime (21689197) 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, 2440 + ... + 7023.

It is an arithmetic number, because the mean of its divisors is an integer number (2119936).

Almost surely, 2^21689196 is an apocalyptic number.

It is an amenable number.

21689196 is an abundant number, since it is smaller than the sum of its proper divisors (29189268).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21689196 is a wasteful number, since it uses less digits than its factorization.

21689196 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9661 (or 9659 counting only the distinct ones).

The product of its digits is 46656, while the sum is 42.

The square root of 21689196 is about 4657.1660910902. The cubic root of 21689196 is about 278.8781472230.

The spelling of 21689196 in words is "twenty-one million, six hundred eighty-nine thousand, one hundred ninety-six".