21498672 has 80 divisors (see below), whose sum is σ = 60496128. Its totient is φ = 6539520.

The previous prime is 21498649. The next prime is 21498679. The reversal of 21498672 is 27689412.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a self number, because there is not a number n which added to its sum of digits gives 21498672.

It is not an unprimeable number, because it can be changed into a prime (21498679) 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, 81613 + ... + 81875.

Almost surely, 2^21498672 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 21498672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30248064).

21498672 is an abundant number, since it is smaller than the sum of its proper divisors (38997456).

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

21498672 is a wasteful number, since it uses less digits than its factorization.

21498672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 418 (or 412 counting only the distinct ones).

The product of its digits is 48384, while the sum is 39.

The square root of 21498672 is about 4636.6660436137. Note that the first 3 decimals coincide. The cubic root of 21498672 is about 278.0591630892.

The spelling of 21498672 in words is "twenty-one million, four hundred ninety-eight thousand, six hundred seventy-two".