21940523 has 8 divisors (see below), whose sum is σ = 25343280. Its totient is φ = 18772480.

The previous prime is 21940511. The next prime is 21940537. The reversal of 21940523 is 32504912.

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

It is a cyclic number.

It is not a de Polignac number, because 21940523 - 2⁸ = 21940267 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21940492 and 21940501.

It is not an unprimeable number, because it can be changed into a prime (21940823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 58478 + ... + 58851.

It is an arithmetic number, because the mean of its divisors is an integer number (3167910).

Almost surely, 2^21940523 is an apocalyptic number.

21940523 is a deficient number, since it is larger than the sum of its proper divisors (3402757).

21940523 is a wasteful number, since it uses less digits than its factorization.

21940523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117357.

The product of its (nonzero) digits is 2160, while the sum is 26.

The square root of 21940523 is about 4684.0711992881. The cubic root of 21940523 is about 279.9511947248.

The spelling of 21940523 in words is "twenty-one million, nine hundred forty thousand, five hundred twenty-three".