21498897 has 32 divisors (see below), whose sum is σ = 35424000. Its totient is φ = 11553024.

The previous prime is 21498857. The next prime is 21498907. The reversal of 21498897 is 79889412.

It is not a de Polignac number, because 21498897 - 2⁸ = 21498641 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21498817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 16879 + ... + 18107.

It is an arithmetic number, because the mean of its divisors is an integer number (1107000).

Almost surely, 2^21498897 is an apocalyptic number.

It is an amenable number.

21498897 is a deficient number, since it is larger than the sum of its proper divisors (13925103).

21498897 is a wasteful number, since it uses less digits than its factorization.

21498897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1270 (or 1256 counting only the distinct ones).

The product of its digits is 290304, while the sum is 48.

The square root of 21498897 is about 4636.6903066735. The cubic root of 21498897 is about 278.0601331196.

The spelling of 21498897 in words is "twenty-one million, four hundred ninety-eight thousand, eight hundred ninety-seven".