21830742 has 16 divisors (see below), whose sum is σ = 48512880. Its totient is φ = 7276896.

The previous prime is 21830719. The next prime is 21830759. The reversal of 21830742 is 24703812.

It is a Harshad number since it is a multiple of its sum of digits (27).

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, 202083 + ... + 202190.

It is an arithmetic number, because the mean of its divisors is an integer number (3032055).

Almost surely, 2^21830742 is an apocalyptic number.

21830742 is an abundant number, since it is smaller than the sum of its proper divisors (26682138).

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

21830742 is a wasteful number, since it uses less digits than its factorization.

21830742 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 404284 (or 404278 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 21830742 is about 4672.3379586669. The cubic root of 21830742 is about 279.4834950886.

The spelling of 21830742 in words is "twenty-one million, eight hundred thirty thousand, seven hundred forty-two".