21698264 has 64 divisors (see below), whose sum is σ = 49766400. Its totient is φ = 8668800.

The previous prime is 21698213. The next prime is 21698267. The reversal of 21698264 is 46289612.

It is a super-2 number, since 2×21698264² = 941629321227392, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21698267) 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, 50129 + ... + 50559.

It is an arithmetic number, because the mean of its divisors is an integer number (777600).

Almost surely, 2^21698264 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21698264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24883200).

21698264 is an abundant number, since it is smaller than the sum of its proper divisors (28068136).

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

21698264 is a wasteful number, since it uses less digits than its factorization.

21698264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 504 (or 500 counting only the distinct ones).

The product of its digits is 41472, while the sum is 38.

The square root of 21698264 is about 4658.1395427789. The cubic root of 21698264 is about 278.9170070419.

The spelling of 21698264 in words is "twenty-one million, six hundred ninety-eight thousand, two hundred sixty-four".