21373858 has 16 divisors (see below), whose sum is σ = 35109216. Its totient is φ = 9678240.

The previous prime is 21373843. The next prime is 21373867. The reversal of 21373858 is 85837312.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4510 + ... + 7942.

It is an arithmetic number, because the mean of its divisors is an integer number (2194326).

Almost surely, 2^21373858 is an apocalyptic number.

21373858 is a deficient number, since it is larger than the sum of its proper divisors (13735358).

21373858 is a wasteful number, since it uses less digits than its factorization.

21373858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3729.

The product of its digits is 40320, while the sum is 37.

The square root of 21373858 is about 4623.1869960018. The cubic root of 21373858 is about 277.5200126248.

It can be divided in two parts, 2137 and 3858, that added together give a palindrome (5995).

The spelling of 21373858 in words is "twenty-one million, three hundred seventy-three thousand, eight hundred fifty-eight".