405516815261 has 2 divisors, whose sum is σ = 405516815262. Its totient is φ = 405516815260.

The previous prime is 405516815239. The next prime is 405516815317. The reversal of 405516815261 is 162518615504.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 340975412761 + 64541402500 = 583931^2 + 254050^2 .

It is a cyclic number.

It is not a de Polignac number, because 405516815261 - 2³⁴ = 388336946077 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (405516415261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202758407630 + 202758407631.

It is an arithmetic number, because the mean of its divisors is an integer number (202758407631).

Almost surely, 2^405516815261 is an apocalyptic number.

It is an amenable number.

405516815261 is a deficient number, since it is larger than the sum of its proper divisors (1).

405516815261 is an equidigital number, since it uses as much as digits as its factorization.

405516815261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288000, while the sum is 44.

The spelling of 405516815261 in words is "four hundred five billion, five hundred sixteen million, eight hundred fifteen thousand, two hundred sixty-one".