21984830 has 24 divisors (see below), whose sum is σ = 46034568. Its totient is φ = 7537488.

The previous prime is 21984829. The next prime is 21984857. The reversal of 21984830 is 3848912.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21944 + ... + 22923.

It is an arithmetic number, because the mean of its divisors is an integer number (1918107).

Almost surely, 2^21984830 is an apocalyptic number.

21984830 is an abundant number, since it is smaller than the sum of its proper divisors (24049738).

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

21984830 is a wasteful number, since it uses less digits than its factorization.

21984830 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44888 (or 44881 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 21984830 is about 4688.7983535230. The cubic root of 21984830 is about 280.1395138071.

The spelling of 21984830 in words is "twenty-one million, nine hundred eighty-four thousand, eight hundred thirty".