31511225461 has 2 divisors, whose sum is σ = 31511225462. Its totient is φ = 31511225460.

The previous prime is 31511225413. The next prime is 31511225489. The reversal of 31511225461 is 16452211513.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30453740100 + 1057485361 = 174510^2 + 32519^2 .

It is a cyclic number.

It is not a de Polignac number, because 31511225461 - 2³³ = 22921290869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31511225411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15755612730 + 15755612731.

It is an arithmetic number, because the mean of its divisors is an integer number (15755612731).

Almost surely, 2^31511225461 is an apocalyptic number.

It is an amenable number.

31511225461 is a deficient number, since it is larger than the sum of its proper divisors (1).

31511225461 is an equidigital number, since it uses as much as digits as its factorization.

31511225461 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7200, while the sum is 31.

Adding to 31511225461 its reverse (16452211513), we get a palindrome (47963436974).

The spelling of 31511225461 in words is "thirty-one billion, five hundred eleven million, two hundred twenty-five thousand, four hundred sixty-one".