1215555500609 has 2 divisors, whose sum is σ = 1215555500610. Its totient is φ = 1215555500608.

The previous prime is 1215555500587. The next prime is 1215555500629. The reversal of 1215555500609 is 9060055555121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1212156960400 + 3398540209 = 1100980^2 + 58297^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1215555500609 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1215555500609.

It is not a weakly prime, because it can be changed into another prime (1215555500629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 607777750304 + 607777750305.

It is an arithmetic number, because the mean of its divisors is an integer number (607777750305).

Almost surely, 2^{1215555500609} is an apocalyptic number.

It is an amenable number.

1215555500609 is a deficient number, since it is larger than the sum of its proper divisors (1).

1215555500609 is an equidigital number, since it uses as much as digits as its factorization.

1215555500609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 337500, while the sum is 44.

The spelling of 1215555500609 in words is "one trillion, two hundred fifteen billion, five hundred fifty-five million, five hundred thousand, six hundred nine".