21262258 has 16 divisors (see below), whose sum is σ = 33379776. Its totient is φ = 10138480.

The previous prime is 21262247. The next prime is 21262289. The reversal of 21262258 is 85226212.

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 7 ways as a sum of consecutive naturals, for example, 25488 + ... + 26308.

It is an arithmetic number, because the mean of its divisors is an integer number (2086236).

Almost surely, 2^21262258 is an apocalyptic number.

21262258 is a deficient number, since it is larger than the sum of its proper divisors (12117518).

21262258 is a wasteful number, since it uses less digits than its factorization.

21262258 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1409.

The product of its digits is 3840, while the sum is 28.

The square root of 21262258 is about 4611.1016037385. The cubic root of 21262258 is about 277.0361615265.

The spelling of 21262258 in words is "twenty-one million, two hundred sixty-two thousand, two hundred fifty-eight".