3891731513 has 2 divisors, whose sum is σ = 3891731514. Its totient is φ = 3891731512.

The previous prime is 3891731483. The next prime is 3891731533. The reversal of 3891731513 is 3151371983.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3706009129 + 185722384 = 60877^2 + 13628^2 .

It is a cyclic number.

It is not a de Polignac number, because 3891731513 - 2¹⁰ = 3891730489 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (3891731533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1945865756 + 1945865757.

It is an arithmetic number, because the mean of its divisors is an integer number (1945865757).

Almost surely, 2^3891731513 is an apocalyptic number.

It is an amenable number.

3891731513 is a deficient number, since it is larger than the sum of its proper divisors (1).

3891731513 is an equidigital number, since it uses as much as digits as its factorization.

3891731513 is an evil number, because the sum of its binary digits is even.

The product of its digits is 68040, while the sum is 41.

The square root of 3891731513 is about 62383.7439803031. The cubic root of 3891731513 is about 1572.9477276608.

The spelling of 3891731513 in words is "three billion, eight hundred ninety-one million, seven hundred thirty-one thousand, five hundred thirteen".