21149718 has 32 divisors (see below), whose sum is σ = 44388864. Its totient is φ = 6710112.

The previous prime is 21149699. The next prime is 21149731. The reversal of 21149718 is 81794112.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9421 + ... + 11447.

It is an arithmetic number, because the mean of its divisors is an integer number (1387152).

Almost surely, 2^21149718 is an apocalyptic number.

21149718 is an abundant number, since it is smaller than the sum of its proper divisors (23239146).

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

21149718 is a wasteful number, since it uses less digits than its factorization.

21149718 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2116.

The product of its digits is 4032, while the sum is 33.

The square root of 21149718 is about 4598.8822555051. The cubic root of 21149718 is about 276.5465174013.

The spelling of 21149718 in words is "twenty-one million, one hundred forty-nine thousand, seven hundred eighteen".