21908898 has 24 divisors (see below), whose sum is σ = 51785136. Its totient is φ = 6639000.

The previous prime is 21908851. The next prime is 21908899. The reversal of 21908898 is 89880912.

It is not an unprimeable number, because it can be changed into a prime (21908899) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 55128 + ... + 55523.

It is an arithmetic number, because the mean of its divisors is an integer number (2157714).

Almost surely, 2^21908898 is an apocalyptic number.

21908898 is an abundant number, since it is smaller than the sum of its proper divisors (29876238).

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

21908898 is a wasteful number, since it uses less digits than its factorization.

21908898 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110670 (or 110667 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 45.

The square root of 21908898 is about 4680.6941792858. The cubic root of 21908898 is about 279.8166231268.

The spelling of 21908898 in words is "twenty-one million, nine hundred eight thousand, eight hundred ninety-eight".