21246180 has 48 divisors (see below), whose sum is σ = 62623680. Its totient is φ = 5367168.

The previous prime is 21246179. The next prime is 21246187. The reversal of 21246180 is 8164212.

It is a self number, because there is not a number n which added to its sum of digits gives 21246180.

It is not an unprimeable number, because it can be changed into a prime (21246187) 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, 8179 + ... + 10458.

It is an arithmetic number, because the mean of its divisors is an integer number (1304660).

Almost surely, 2^21246180 is an apocalyptic number.

21246180 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21246180 is an abundant number, since it is smaller than the sum of its proper divisors (41377500).

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

21246180 is a wasteful number, since it uses less digits than its factorization.

21246180 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18668 (or 18666 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 24.

The square root of 21246180 is about 4609.3578728495. The cubic root of 21246180 is about 276.9663145925.

The spelling of 21246180 in words is "twenty-one million, two hundred forty-six thousand, one hundred eighty".