21354923 has 8 divisors (see below), whose sum is σ = 21665280. Its totient is φ = 21047040.

The previous prime is 21354913. The next prime is 21354943. The reversal of 21354923 is 32945312.

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 21354923 - 2⁶ = 21354859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21354913) 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, 22523 + ... + 23451.

It is an arithmetic number, because the mean of its divisors is an integer number (2708160).

Almost surely, 2^21354923 is an apocalyptic number.

21354923 is a deficient number, since it is larger than the sum of its proper divisors (310357).

21354923 is a wasteful number, since it uses less digits than its factorization.

21354923 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1237.

The product of its digits is 6480, while the sum is 29.

The square root of 21354923 is about 4621.1387124820. The cubic root of 21354923 is about 277.4380371894.

The spelling of 21354923 in words is "twenty-one million, three hundred fifty-four thousand, nine hundred twenty-three".