21337723 has 8 divisors (see below), whose sum is σ = 23558976. Its totient is φ = 19163400.

The previous prime is 21337717. The next prime is 21337733. The reversal of 21337723 is 32773312.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21337723 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21337691 and 21337700.

It is not an unprimeable number, because it can be changed into a prime (21337733) 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, 10773 + ... + 12598.

It is an arithmetic number, because the mean of its divisors is an integer number (2944872).

Almost surely, 2^21337723 is an apocalyptic number.

21337723 is a deficient number, since it is larger than the sum of its proper divisors (2221253).

21337723 is a wasteful number, since it uses less digits than its factorization.

21337723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23465.

The product of its digits is 5292, while the sum is 28.

The square root of 21337723 is about 4619.2773244307. The cubic root of 21337723 is about 277.3635310911.

The spelling of 21337723 in words is "twenty-one million, three hundred thirty-seven thousand, seven hundred twenty-three".