31138732549 has 2 divisors, whose sum is σ = 31138732550. Its totient is φ = 31138732548.

The previous prime is 31138732523. The next prime is 31138732577. The reversal of 31138732549 is 94523783113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29683844100 + 1454888449 = 172290^2 + 38143^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31138732549 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31138732499 and 31138732508.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31138732589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15569366274 + 15569366275.

It is an arithmetic number, because the mean of its divisors is an integer number (15569366275).

Almost surely, 2^31138732549 is an apocalyptic number.

It is an amenable number.

31138732549 is a deficient number, since it is larger than the sum of its proper divisors (1).

31138732549 is an equidigital number, since it uses as much as digits as its factorization.

31138732549 is an evil number, because the sum of its binary digits is even.

The product of its digits is 544320, while the sum is 46.

The spelling of 31138732549 in words is "thirty-one billion, one hundred thirty-eight million, seven hundred thirty-two thousand, five hundred forty-nine".