21999458 has 32 divisors (see below), whose sum is σ = 37195200. Its totient is φ = 9688896.

The previous prime is 21999449. The next prime is 21999463. The reversal of 21999458 is 85499912.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 122813 + ... + 122991.

It is an arithmetic number, because the mean of its divisors is an integer number (1162350).

Almost surely, 2^21999458 is an apocalyptic number.

21999458 is a deficient number, since it is larger than the sum of its proper divisors (15195742).

21999458 is a wasteful number, since it uses less digits than its factorization.

21999458 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 386.

The product of its digits is 233280, while the sum is 47.

The square root of 21999458 is about 4690.3579820734. The cubic root of 21999458 is about 280.2016319780.

The spelling of 21999458 in words is "twenty-one million, nine hundred ninety-nine thousand, four hundred fifty-eight".