615211607261 has 2 divisors, whose sum is σ = 615211607262. Its totient is φ = 615211607260.

The previous prime is 615211607137. The next prime is 615211607267. The reversal of 615211607261 is 162706112516.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 557980614361 + 57230992900 = 746981^2 + 239230^2 .

It is a cyclic number.

It is not a de Polignac number, because 615211607261 - 2³⁰ = 614137865437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (615211607267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 307605803630 + 307605803631.

It is an arithmetic number, because the mean of its divisors is an integer number (307605803631).

Almost surely, 2^615211607261 is an apocalyptic number.

It is an amenable number.

615211607261 is a deficient number, since it is larger than the sum of its proper divisors (1).

615211607261 is an equidigital number, since it uses as much as digits as its factorization.

615211607261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 30240, while the sum is 38.

Adding to 615211607261 its reverse (162706112516), we get a palindrome (777917719777).

The spelling of 615211607261 in words is "six hundred fifteen billion, two hundred eleven million, six hundred seven thousand, two hundred sixty-one".