21936723 has 8 divisors (see below), whose sum is σ = 29270928. Its totient is φ = 14613504.

The previous prime is 21936701. The next prime is 21936727. The reversal of 21936723 is 32763912.

It is a happy number.

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

It is not a de Polignac number, because 21936723 - 2¹² = 21932627 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21936727) 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, 5211 + ... + 8427.

It is an arithmetic number, because the mean of its divisors is an integer number (3658866).

Almost surely, 2^21936723 is an apocalyptic number.

21936723 is a deficient number, since it is larger than the sum of its proper divisors (7334205).

21936723 is a wasteful number, since it uses less digits than its factorization.

21936723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5493.

The product of its digits is 13608, while the sum is 33.

The square root of 21936723 is about 4683.6655516806. The cubic root of 21936723 is about 279.9350316953.

The spelling of 21936723 in words is "twenty-one million, nine hundred thirty-six thousand, seven hundred twenty-three".