21957003 has 6 divisors (see below), whose sum is σ = 31715684. Its totient is φ = 14637996.

The previous prime is 21956983. The next prime is 21957043. The reversal of 21957003 is 30075912.

It is not a de Polignac number, because 21957003 - 2⁵ = 21956971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21957043) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1219825 + ... + 1219842.

Almost surely, 2^21957003 is an apocalyptic number.

21957003 is a deficient number, since it is larger than the sum of its proper divisors (9758681).

21957003 is a wasteful number, since it uses less digits than its factorization.

21957003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2439673 (or 2439670 counting only the distinct ones).

The product of its (nonzero) digits is 1890, while the sum is 27.

The square root of 21957003 is about 4685.8300225254. The cubic root of 21957003 is about 280.0212696428.

The spelling of 21957003 in words is "twenty-one million, nine hundred fifty-seven thousand, three".