21916097 has 4 divisors (see below), whose sum is σ = 25046976. Its totient is φ = 18785220.

The previous prime is 21916093. The next prime is 21916109. The reversal of 21916097 is 79061912.

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 21916097 - 2² = 21916093 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21916093) 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, 1565429 + ... + 1565442.

It is an arithmetic number, because the mean of its divisors is an integer number (6261744).

Almost surely, 2^21916097 is an apocalyptic number.

It is an amenable number.

21916097 is a deficient number, since it is larger than the sum of its proper divisors (3130879).

21916097 is an equidigital number, since it uses as much as digits as its factorization.

21916097 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3130878.

The product of its (nonzero) digits is 6804, while the sum is 35.

The square root of 21916097 is about 4681.4631259896. The cubic root of 21916097 is about 279.8472678946.

The spelling of 21916097 in words is "twenty-one million, nine hundred sixteen thousand, ninety-seven".