39138491 has 4 divisors (see below), whose sum is σ = 44729712. Its totient is φ = 33547272.

The previous prime is 39138467. The next prime is 39138493. The reversal of 39138491 is 19483193.

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: 19483193 = 751 ⋅25943.

It is a cyclic number.

It is not a de Polignac number, because 39138491 - 2⁶ = 39138427 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (39138493) 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, 2795600 + ... + 2795613.

It is an arithmetic number, because the mean of its divisors is an integer number (11182428).

Almost surely, 2^39138491 is an apocalyptic number.

39138491 is a deficient number, since it is larger than the sum of its proper divisors (5591221).

39138491 is an equidigital number, since it uses as much as digits as its factorization.

39138491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5591220.

The product of its digits is 23328, while the sum is 38.

The square root of 39138491 is about 6256.0763262607. The cubic root of 39138491 is about 339.5220822829.

The spelling of 39138491 in words is "thirty-nine million, one hundred thirty-eight thousand, four hundred ninety-one".