38623721 has 4 divisors (see below), whose sum is σ = 38639700. Its totient is φ = 38607744.

The previous prime is 38623709. The next prime is 38623723. The reversal of 38623721 is 12732683.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12732683 = 1117 ⋅11399.

It can be written as a sum of positive squares in 2 ways, for example, as 2755600 + 35868121 = 1660^2 + 5989^2 .

It is a cyclic number.

It is not a de Polignac number, because 38623721 - 2⁶ = 38623657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (38623723) 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, 3536 + ... + 9473.

It is an arithmetic number, because the mean of its divisors is an integer number (9659925).

Almost surely, 2^38623721 is an apocalyptic number.

It is an amenable number.

38623721 is a deficient number, since it is larger than the sum of its proper divisors (15979).

38623721 is a wasteful number, since it uses less digits than its factorization.

38623721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15978.

The product of its digits is 12096, while the sum is 32.

The square root of 38623721 is about 6214.7985486257. The cubic root of 38623721 is about 338.0269839456.

The spelling of 38623721 in words is "thirty-eight million, six hundred twenty-three thousand, seven hundred twenty-one".