21467897 has 4 divisors (see below), whose sum is σ = 23419536. Its totient is φ = 19516260.

The previous prime is 21467893. The next prime is 21467899. The reversal of 21467897 is 79876412.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21467897 - 2² = 21467893 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21467893) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 975803 + ... + 975824.

It is an arithmetic number, because the mean of its divisors is an integer number (5854884).

Almost surely, 2^21467897 is an apocalyptic number.

It is an amenable number.

21467897 is a deficient number, since it is larger than the sum of its proper divisors (1951639).

21467897 is a wasteful number, since it uses less digits than its factorization.

21467897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1951638.

The product of its digits is 169344, while the sum is 44.

The square root of 21467897 is about 4633.3461990229. The cubic root of 21467897 is about 277.9264206700.

The spelling of 21467897 in words is "twenty-one million, four hundred sixty-seven thousand, eight hundred ninety-seven".