23720621 has 4 divisors (see below), whose sum is σ = 23930652. Its totient is φ = 23510592.

The previous prime is 23720617. The next prime is 23720629. The reversal of 23720621 is 12602732.

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 343396 + 23377225 = 586^2 + 4835^2 .

It is a cyclic number.

It is not a de Polignac number, because 23720621 - 2² = 23720617 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23720629) 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, 104846 + ... + 105071.

It is an arithmetic number, because the mean of its divisors is an integer number (5982663).

Almost surely, 2^23720621 is an apocalyptic number.

It is an amenable number.

23720621 is a deficient number, since it is larger than the sum of its proper divisors (210031).

23720621 is a wasteful number, since it uses less digits than its factorization.

23720621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210030.

The product of its (nonzero) digits is 1008, while the sum is 23.

The square root of 23720621 is about 4870.3820178709. The cubic root of 23720621 is about 287.3262809384.

The spelling of 23720621 in words is "twenty-three million, seven hundred twenty thousand, six hundred twenty-one".