38644991 has 16 divisors (see below), whose sum is σ = 50277888. Its totient is φ = 28802400.

The previous prime is 38644939. The next prime is 38645011. The reversal of 38644991 is 19944683.

It is a de Polignac number, because none of the positive numbers 2^k-38644991 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 (38644891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9140 + ... + 12681.

It is an arithmetic number, because the mean of its divisors is an integer number (3142368).

Almost surely, 2^38644991 is an apocalyptic number.

38644991 is a deficient number, since it is larger than the sum of its proper divisors (11632897).

38644991 is a wasteful number, since it uses less digits than its factorization.

38644991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21862.

The product of its digits is 186624, while the sum is 44.

The square root of 38644991 is about 6216.5095511871. The cubic root of 38644991 is about 338.0890228029.

The spelling of 38644991 in words is "thirty-eight million, six hundred forty-four thousand, nine hundred ninety-one".