21798230 has 8 divisors (see below), whose sum is σ = 39236832. Its totient is φ = 8719288.

The previous prime is 21798221. The next prime is 21798241. The reversal of 21798230 is 3289712.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21798230² = 950325662265800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1089902 + ... + 1089921.

It is an arithmetic number, because the mean of its divisors is an integer number (4904604).

Almost surely, 2^21798230 is an apocalyptic number.

21798230 is a deficient number, since it is larger than the sum of its proper divisors (17438602).

21798230 is a wasteful number, since it uses less digits than its factorization.

21798230 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2179830.

The product of its (nonzero) digits is 6048, while the sum is 32.

The square root of 21798230 is about 4668.8574619493. The cubic root of 21798230 is about 279.3446834695.

The spelling of 21798230 in words is "twenty-one million, seven hundred ninety-eight thousand, two hundred thirty".