39172145 has 4 divisors (see below), whose sum is σ = 47006580. Its totient is φ = 31337712.

The previous prime is 39172123. The next prime is 39172163. The reversal of 39172145 is 54127193.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 54127193 = 137 ⋅395089.

It can be written as a sum of positive squares in 2 ways, for example, as 30481441 + 8690704 = 5521^2 + 2948^2 .

It is a cyclic number.

It is not a de Polignac number, because 39172145 - 2⁸ = 39171889 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3917210 + ... + 3917219.

It is an arithmetic number, because the mean of its divisors is an integer number (11751645).

Almost surely, 2^39172145 is an apocalyptic number.

It is an amenable number.

39172145 is a deficient number, since it is larger than the sum of its proper divisors (7834435).

39172145 is an equidigital number, since it uses as much as digits as its factorization.

39172145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7834434.

The product of its digits is 7560, while the sum is 32.

The square root of 39172145 is about 6258.7654533462. The cubic root of 39172145 is about 339.6193693132.

The spelling of 39172145 in words is "thirty-nine million, one hundred seventy-two thousand, one hundred forty-five".