21867897 has 12 divisors (see below), whose sum is σ = 29495760. Its totient is φ = 14410512.

The previous prime is 21867869. The next prime is 21867913. The reversal of 21867897 is 79876812.

It is not a de Polignac number, because 21867897 - 2¹² = 21863801 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21867497) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 95379 + ... + 95607.

It is an arithmetic number, because the mean of its divisors is an integer number (2457980).

Almost surely, 2^21867897 is an apocalyptic number.

It is an amenable number.

21867897 is a deficient number, since it is larger than the sum of its proper divisors (7627863).

21867897 is an equidigital number, since it uses as much as digits as its factorization.

21867897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 600 (or 371 counting only the distinct ones).

The product of its digits is 338688, while the sum is 48.

The square root of 21867897 is about 4676.3123291756. The cubic root of 21867897 is about 279.6419615860.

The spelling of 21867897 in words is "twenty-one million, eight hundred sixty-seven thousand, eight hundred ninety-seven".