39915251993 has 4 divisors (see below), whose sum is σ = 39935484708. Its totient is φ = 39895019280.

The previous prime is 39915251947. The next prime is 39915252031.

39915251993 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15768578329 + 24146673664 = 125573^2 + 155392^2 .

It is a cyclic number.

It is not a de Polignac number, because 39915251993 - 2¹⁶ = 39915186457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (39915251923) 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, 10113398 + ... + 10117343.

It is an arithmetic number, because the mean of its divisors is an integer number (9983871177).

Almost surely, 2^39915251993 is an apocalyptic number.

It is an amenable number.

39915251993 is a deficient number, since it is larger than the sum of its proper divisors (20232715).

39915251993 is a wasteful number, since it uses less digits than its factorization.

39915251993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20232714.

The product of its digits is 2952450, while the sum is 56.

The spelling of 39915251993 in words is "thirty-nine billion, nine hundred fifteen million, two hundred fifty-one thousand, nine hundred ninety-three".