21898835 has 24 divisors (see below), whose sum is σ = 30919200. Its totient is φ = 14883456.

The previous prime is 21898801. The next prime is 21898837. The reversal of 21898835 is 53889812.

It is not a de Polignac number, because 21898835 - 2¹⁸ = 21636691 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21898837) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 193739 + ... + 193851.

It is an arithmetic number, because the mean of its divisors is an integer number (1288300).

Almost surely, 2^21898835 is an apocalyptic number.

21898835 is a deficient number, since it is larger than the sum of its proper divisors (9020365).

21898835 is an frugal number, since it uses more digits than its factorization.

21898835 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 252 (or 125 counting only the distinct ones).

The product of its digits is 138240, while the sum is 44.

The square root of 21898835 is about 4679.6191084318. The cubic root of 21898835 is about 279.7737756059.

The spelling of 21898835 in words is "twenty-one million, eight hundred ninety-eight thousand, eight hundred thirty-five".