21372753 has 8 divisors (see below), whose sum is σ = 28964416. Its totient is φ = 14014800.

The previous prime is 21372737. The next prime is 21372761. The reversal of 21372753 is 35727312.

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

It is not a de Polignac number, because 21372753 - 2⁴ = 21372737 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 21372753.

It is not an unprimeable number, because it can be changed into a prime (21372713) 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, 58213 + ... + 58578.

It is an arithmetic number, because the mean of its divisors is an integer number (3620552).

Almost surely, 2^21372753 is an apocalyptic number.

It is an amenable number.

21372753 is a deficient number, since it is larger than the sum of its proper divisors (7591663).

21372753 is a wasteful number, since it uses less digits than its factorization.

21372753 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116855.

The product of its digits is 8820, while the sum is 30.

The square root of 21372753 is about 4623.0674881511. The cubic root of 21372753 is about 277.5152300707.

It can be divided in two parts, 2137275 and 3, that added together give a triangular number (2137278 = T₂₀₆₇).

The spelling of 21372753 in words is "twenty-one million, three hundred seventy-two thousand, seven hundred fifty-three".