21943117 has 8 divisors (see below), whose sum is σ = 25308800. Its totient is φ = 18635184.

The previous prime is 21943099. The next prime is 21943171. The reversal of 21943117 is 71134912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21943117 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 (21943177) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13617 + ... + 15142.

It is an arithmetic number, because the mean of its divisors is an integer number (3163600).

Almost surely, 2^21943117 is an apocalyptic number.

It is an amenable number.

21943117 is a deficient number, since it is larger than the sum of its proper divisors (3365683).

21943117 is a wasteful number, since it uses less digits than its factorization.

21943117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28875.

The product of its digits is 1512, while the sum is 28.

The square root of 21943117 is about 4684.3480869807. The cubic root of 21943117 is about 279.9622270474.

The spelling of 21943117 in words is "twenty-one million, nine hundred forty-three thousand, one hundred seventeen".