261531370137053 has 2 divisors, whose sum is σ = 261531370137054. Its totient is φ = 261531370137052.

The previous prime is 261531370137031. The next prime is 261531370137067. The reversal of 261531370137053 is 350731073135162.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 251164238778244 + 10367131358809 = 15848162^2 + 3219803^2 .

It is a cyclic number.

It is not a de Polignac number, because 261531370137053 - 2¹⁸ = 261531369874909 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 261531370136989 and 261531370137007.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261531370137013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130765685068526 + 130765685068527.

It is an arithmetic number, because the mean of its divisors is an integer number (130765685068527).

Almost surely, 2^{261531370137053} is an apocalyptic number.

It is an amenable number.

261531370137053 is a deficient number, since it is larger than the sum of its proper divisors (1).

261531370137053 is an equidigital number, since it uses as much as digits as its factorization.

261531370137053 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1190700, while the sum is 47.

The spelling of 261531370137053 in words is "two hundred sixty-one trillion, five hundred thirty-one billion, three hundred seventy million, one hundred thirty-seven thousand, fifty-three".