1561326862259 has 2 divisors, whose sum is σ = 1561326862260. Its totient is φ = 1561326862258.

The previous prime is 1561326862229. The next prime is 1561326862261. The reversal of 1561326862259 is 9522686231651.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1561326862259 - 2³² = 1557031894963 is a prime.

Together with 1561326862261, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1561326862229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 780663431129 + 780663431130.

It is an arithmetic number, because the mean of its divisors is an integer number (780663431130).

Almost surely, 2^{1561326862259} is an apocalyptic number.

1561326862259 is a deficient number, since it is larger than the sum of its proper divisors (1).

1561326862259 is an equidigital number, since it uses as much as digits as its factorization.

1561326862259 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9331200, while the sum is 56.

The spelling of 1561326862259 in words is "one trillion, five hundred sixty-one billion, three hundred twenty-six million, eight hundred sixty-two thousand, two hundred fifty-nine".