21744774 has 20 divisors (see below), whose sum is σ = 48724764. Its totient is φ = 7248204.

The previous prime is 21744763. The next prime is 21744803. The reversal of 21744774 is 47744712.

It is a super-2 number, since 2×21744774² = 945670392622152, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 66952 + ... + 67275.

Almost surely, 2^21744774 is an apocalyptic number.

21744774 is an abundant number, since it is smaller than the sum of its proper divisors (26979990).

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

21744774 is a wasteful number, since it uses less digits than its factorization.

21744774 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134241 (or 134232 counting only the distinct ones).

The product of its digits is 43904, while the sum is 36.

The square root of 21744774 is about 4663.1292068739. The cubic root of 21744774 is about 279.1161500435.

The spelling of 21744774 in words is "twenty-one million, seven hundred forty-four thousand, seven hundred seventy-four".