39640157 has 4 divisors (see below), whose sum is σ = 39706716. Its totient is φ = 39573600.

The previous prime is 39640151. The next prime is 39640217. The reversal of 39640157 is 75104693.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75104693 = 29 ⋅2589817.

It can be written as a sum of positive squares in 2 ways, for example, as 27730756 + 11909401 = 5266^2 + 3451^2 .

It is a cyclic number.

It is not a de Polignac number, because 39640157 - 2¹⁶ = 39574621 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 (39640151) 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, 32378 + ... + 33579.

It is an arithmetic number, because the mean of its divisors is an integer number (9926679).

Almost surely, 2^39640157 is an apocalyptic number.

It is an amenable number.

39640157 is a deficient number, since it is larger than the sum of its proper divisors (66559).

39640157 is an equidigital number, since it uses as much as digits as its factorization.

39640157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66558.

The product of its (nonzero) digits is 22680, while the sum is 35.

The square root of 39640157 is about 6296.0429636399. The cubic root of 39640157 is about 340.9665604760.

The spelling of 39640157 in words is "thirty-nine million, six hundred forty thousand, one hundred fifty-seven".