21903753 has 8 divisors (see below), whose sum is σ = 29226688. Its totient is φ = 14591664.

The previous prime is 21903737. The next prime is 21903779. The reversal of 21903753 is 35730912.

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

It is not a de Polignac number, because 21903753 - 2⁴ = 21903737 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21903753.

It is not an unprimeable number, because it can be changed into a prime (21903733) 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, 6051 + ... + 8967.

It is an arithmetic number, because the mean of its divisors is an integer number (3653336).

Almost surely, 2^21903753 is an apocalyptic number.

It is an amenable number.

21903753 is a deficient number, since it is larger than the sum of its proper divisors (7322935).

21903753 is a wasteful number, since it uses less digits than its factorization.

21903753 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5423.

The product of its (nonzero) digits is 5670, while the sum is 30.

The square root of 21903753 is about 4680.1445490497. The cubic root of 21903753 is about 279.7947177312.

The spelling of 21903753 in words is "twenty-one million, nine hundred three thousand, seven hundred fifty-three".