38640405 has 16 divisors (see below), whose sum is σ = 65461824. Its totient is φ = 19395840.

The previous prime is 38640403. The next prime is 38640419. The reversal of 38640405 is 50404683.

38640405 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 38640405 - 2¹ = 38640403 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (38640403) 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 15 ways as a sum of consecutive naturals, for example, 75511 + ... + 76020.

It is an arithmetic number, because the mean of its divisors is an integer number (4091364).

Almost surely, 2^38640405 is an apocalyptic number.

It is an amenable number.

38640405 is a deficient number, since it is larger than the sum of its proper divisors (26821419).

38640405 is a wasteful number, since it uses less digits than its factorization.

38640405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151556.

The product of its (nonzero) digits is 11520, while the sum is 30.

The square root of 38640405 is about 6216.1406837362. The cubic root of 38640405 is about 338.0756486022.

The spelling of 38640405 in words is "thirty-eight million, six hundred forty thousand, four hundred five".