21696085 has 4 divisors (see below), whose sum is σ = 26035308. Its totient is φ = 17356864.

The previous prime is 21696083. The next prime is 21696121. The reversal of 21696085 is 58069612.

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

It can be written as a sum of positive squares in 2 ways, for example, as 15350724 + 6345361 = 3918^2 + 2519^2 .

It is a cyclic number.

It is not a de Polignac number, because 21696085 - 2¹ = 21696083 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 (21696083) 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, 2169604 + ... + 2169613.

It is an arithmetic number, because the mean of its divisors is an integer number (6508827).

Almost surely, 2^21696085 is an apocalyptic number.

It is an amenable number.

21696085 is a deficient number, since it is larger than the sum of its proper divisors (4339223).

21696085 is an equidigital number, since it uses as much as digits as its factorization.

21696085 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4339222.

The product of its (nonzero) digits is 25920, while the sum is 37.

The square root of 21696085 is about 4657.9056452444. The cubic root of 21696085 is about 278.9076701890.

The spelling of 21696085 in words is "twenty-one million, six hundred ninety-six thousand, eighty-five".