23797721 has 4 divisors (see below), whose sum is σ = 24033444. Its totient is φ = 23562000.

The previous prime is 23797693. The next prime is 23797757. The reversal of 23797721 is 12779732.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13039321 + 10758400 = 3611^2 + 3280^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-23797721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (23797021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 117710 + ... + 117911.

It is an arithmetic number, because the mean of its divisors is an integer number (6008361).

Almost surely, 2^23797721 is an apocalyptic number.

It is an amenable number.

23797721 is a deficient number, since it is larger than the sum of its proper divisors (235723).

23797721 is a wasteful number, since it uses less digits than its factorization.

23797721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235722.

The product of its digits is 37044, while the sum is 38.

The square root of 23797721 is about 4878.2907867408. The cubic root of 23797721 is about 287.6372466321.

The spelling of 23797721 in words is "twenty-three million, seven hundred ninety-seven thousand, seven hundred twenty-one".