21492180 has 72 divisors (see below), whose sum is σ = 65738400. Its totient is φ = 5683392.

The previous prime is 21492167. The next prime is 21492203. The reversal of 21492180 is 8129412.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 24591 + ... + 25449.

Almost surely, 2^21492180 is an apocalyptic number.

21492180 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21492180, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32869200).

21492180 is an abundant number, since it is smaller than the sum of its proper divisors (44246220).

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

21492180 is a wasteful number, since it uses less digits than its factorization.

21492180 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1013 (or 1008 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 21492180 is about 4635.9659187703. The cubic root of 21492180 is about 278.0311715646.

The spelling of 21492180 in words is "twenty-one million, four hundred ninety-two thousand, one hundred eighty".