21633430 has 32 divisors (see below), whose sum is σ = 47928384. Its totient is φ = 6846336.

The previous prime is 21633427. The next prime is 21633499. The reversal of 21633430 is 3433612.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10977 + ... + 12796.

It is an arithmetic number, because the mean of its divisors is an integer number (1497762).

Almost surely, 2^21633430 is an apocalyptic number.

21633430 is an abundant number, since it is smaller than the sum of its proper divisors (26294954).

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

21633430 is a wasteful number, since it uses less digits than its factorization.

21633430 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23800.

The product of its (nonzero) digits is 1296, while the sum is 22.

The square root of 21633430 is about 4651.1751203325. The cubic root of 21633430 is about 278.6389303250.

The spelling of 21633430 in words is "twenty-one million, six hundred thirty-three thousand, four hundred thirty".