21895967 has 4 divisors (see below), whose sum is σ = 21954120. Its totient is φ = 21837816.

The previous prime is 21895933. The next prime is 21895969. The reversal of 21895967 is 76959812.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21895967 - 2¹² = 21891871 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21895969) 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, 28508 + ... + 29265.

It is an arithmetic number, because the mean of its divisors is an integer number (5488530).

Almost surely, 2^21895967 is an apocalyptic number.

21895967 is a deficient number, since it is larger than the sum of its proper divisors (58153).

21895967 is an equidigital number, since it uses as much as digits as its factorization.

21895967 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58152.

The product of its digits is 272160, while the sum is 47.

The square root of 21895967 is about 4679.3126632017. The cubic root of 21895967 is about 279.7615614672.

The spelling of 21895967 in words is "twenty-one million, eight hundred ninety-five thousand, nine hundred sixty-seven".