21105898 has 16 divisors (see below), whose sum is σ = 35380800. Its totient is φ = 9359200.

The previous prime is 21105863. The next prime is 21105907. The reversal of 21105898 is 89850112.

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, 10798 + ... + 12601.

It is an arithmetic number, because the mean of its divisors is an integer number (2211300).

Almost surely, 2^21105898 is an apocalyptic number.

21105898 is a deficient number, since it is larger than the sum of its proper divisors (14274902).

21105898 is a wasteful number, since it uses less digits than its factorization.

21105898 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23453.

The product of its (nonzero) digits is 5760, while the sum is 34.

The square root of 21105898 is about 4594.1155840923. The cubic root of 21105898 is about 276.3553935401.

It can be divided in two parts, 2110 and 5898, that added together give a palindrome (8008).

The spelling of 21105898 in words is "twenty-one million, one hundred five thousand, eight hundred ninety-eight".