731515993 has 6 divisors (see below), whose sum is σ = 792115134. Its totient is φ = 675245376.

The previous prime is 731515987. The next prime is 731516003. The reversal of 731515993 is 399515137.

It can be written as a sum of positive squares in 3 ways, for example, as 10969344 + 720546649 = 3312^2 + 26843^2 .

It is a de Polignac number, because none of the positive numbers 2^k-731515993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (731515093) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2164080 + ... + 2164417.

It is an arithmetic number, because the mean of its divisors is an integer number (132019189).

Almost surely, 2^731515993 is an apocalyptic number.

It is an amenable number.

731515993 is a deficient number, since it is larger than the sum of its proper divisors (60599141).

731515993 is a wasteful number, since it uses less digits than its factorization.

731515993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4328523 (or 4328510 counting only the distinct ones).

The product of its digits is 127575, while the sum is 43.

The square root of 731515993 is about 27046.5523311198. The cubic root of 731515993 is about 901.0341992018.

The spelling of 731515993 in words is "seven hundred thirty-one million, five hundred fifteen thousand, nine hundred ninety-three".