21423774 has 16 divisors (see below), whose sum is σ = 45368208. Its totient is φ = 6721152.

The previous prime is 21423769. The next prime is 21423781. The reversal of 21423774 is 47732412.

It is a congruent 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, 104917 + ... + 105120.

It is an arithmetic number, because the mean of its divisors is an integer number (2835513).

Almost surely, 2^21423774 is an apocalyptic number.

21423774 is an abundant number, since it is smaller than the sum of its proper divisors (23944434).

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

21423774 is a wasteful number, since it uses less digits than its factorization.

21423774 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210059.

The product of its digits is 9408, while the sum is 30.

The square root of 21423774 is about 4628.5822883470. The cubic root of 21423774 is about 277.7358825467.

The spelling of 21423774 in words is "twenty-one million, four hundred twenty-three thousand, seven hundred seventy-four".