21694017 has 16 divisors (see below), whose sum is σ = 30205440. Its totient is φ = 13833600.

The previous prime is 21694009. The next prime is 21694031. The reversal of 21694017 is 71049612.

It is a happy number.

It is not a de Polignac number, because 21694017 - 2³ = 21694009 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21694007) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6967 + ... + 9587.

It is an arithmetic number, because the mean of its divisors is an integer number (1887840).

Almost surely, 2^21694017 is an apocalyptic number.

It is an amenable number.

21694017 is a deficient number, since it is larger than the sum of its proper divisors (8511423).

21694017 is a wasteful number, since it uses less digits than its factorization.

21694017 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2744.

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 21694017 is about 4657.6836517737. The cubic root of 21694017 is about 278.8988083845.

The spelling of 21694017 in words is "twenty-one million, six hundred ninety-four thousand, seventeen".