21180914 has 8 divisors (see below), whose sum is σ = 31799388. Its totient is φ = 10581120.

The previous prime is 21180893. The next prime is 21180917. The reversal of 21180914 is 41908112.

It can be written as a sum of positive squares in 2 ways, for example, as 19404025 + 1776889 = 4405^2 + 1333^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21180914² = 897262235750792, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21180917) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1367 + ... + 6650.

Almost surely, 2^21180914 is an apocalyptic number.

21180914 is a deficient number, since it is larger than the sum of its proper divisors (10618474).

21180914 is a wasteful number, since it uses less digits than its factorization.

21180914 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9340.

The product of its (nonzero) digits is 576, while the sum is 26.

The square root of 21180914 is about 4602.2726994388. The cubic root of 21180914 is about 276.6824200317.

The spelling of 21180914 in words is "twenty-one million, one hundred eighty thousand, nine hundred fourteen".