21994874 has 16 divisors (see below), whose sum is σ = 36205920. Its totient is φ = 9938160.

The previous prime is 21994867. The next prime is 21994897. The reversal of 21994874 is 47849912.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 917 + ... + 6695.

It is an arithmetic number, because the mean of its divisors is an integer number (2262870).

Almost surely, 2^21994874 is an apocalyptic number.

21994874 is a deficient number, since it is larger than the sum of its proper divisors (14211046).

21994874 is a wasteful number, since it uses less digits than its factorization.

21994874 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5965.

The product of its digits is 145152, while the sum is 44.

The square root of 21994874 is about 4689.8692945540. The cubic root of 21994874 is about 280.1821688696.

It can be divided in two parts, 219948 and 74, that added together give a palindrome (220022).

The spelling of 21994874 in words is "twenty-one million, nine hundred ninety-four thousand, eight hundred seventy-four".