31138732577 has 2 divisors, whose sum is σ = 31138732578. Its totient is φ = 31138732576.

The previous prime is 31138732549. The next prime is 31138732589. The reversal of 31138732577 is 77523783113.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27132348961 + 4006383616 = 164719^2 + 63296^2 .

It is a cyclic number.

It is not a de Polignac number, because 31138732577 - 2¹⁰ = 31138731553 is a prime.

It is not a weakly prime, because it can be changed into another prime (31138732777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15569366288 + 15569366289.

It is an arithmetic number, because the mean of its divisors is an integer number (15569366289).

Almost surely, 2^31138732577 is an apocalyptic number.

It is an amenable number.

31138732577 is a deficient number, since it is larger than the sum of its proper divisors (1).

31138732577 is an equidigital number, since it uses as much as digits as its factorization.

31138732577 is an evil number, because the sum of its binary digits is even.

The product of its digits is 740880, while the sum is 47.

The spelling of 31138732577 in words is "thirty-one billion, one hundred thirty-eight million, seven hundred thirty-two thousand, five hundred seventy-seven".