38388721 has 32 divisors (see below), whose sum is σ = 49248000. Its totient is φ = 29175552.

The previous prime is 38388689. The next prime is 38388731. The reversal of 38388721 is 12788383.

38388721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 38388721 - 2⁵ = 38388689 is a prime.

It is not an unprimeable number, because it can be changed into a prime (38388731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 142575 + ... + 142843.

It is an arithmetic number, because the mean of its divisors is an integer number (1539000).

Almost surely, 2^38388721 is an apocalyptic number.

It is an amenable number.

38388721 is a deficient number, since it is larger than the sum of its proper divisors (10859279).

38388721 is a wasteful number, since it uses less digits than its factorization.

38388721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 361.

The product of its digits is 64512, while the sum is 40.

The square root of 38388721 is about 6195.8632166955. The cubic root of 38388721 is about 337.3400313687.

The spelling of 38388721 in words is "thirty-eight million, three hundred eighty-eight thousand, seven hundred twenty-one".