21898470 has 32 divisors (see below), whose sum is σ = 57335040. Its totient is φ = 5308640.

The previous prime is 21898453. The next prime is 21898501. The reversal of 21898470 is 7489812.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32850 + ... + 33509.

It is an arithmetic number, because the mean of its divisors is an integer number (1791720).

Almost surely, 2^21898470 is an apocalyptic number.

21898470 is an abundant number, since it is smaller than the sum of its proper divisors (35436570).

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

21898470 is a wasteful number, since it uses less digits than its factorization.

21898470 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66380.

The product of its (nonzero) digits is 32256, while the sum is 39.

The square root of 21898470 is about 4679.5801093688. The cubic root of 21898470 is about 279.7722212158.

The spelling of 21898470 in words is "twenty-one million, eight hundred ninety-eight thousand, four hundred seventy".