1561001016139 has 2 divisors, whose sum is σ = 1561001016140. Its totient is φ = 1561001016138.

The previous prime is 1561001016089. The next prime is 1561001016181. The reversal of 1561001016139 is 9316101001651.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1561001016139 - 2⁹ = 1561001015627 is a prime.

It is not a weakly prime, because it can be changed into another prime (1561001013139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 780500508069 + 780500508070.

It is an arithmetic number, because the mean of its divisors is an integer number (780500508070).

Almost surely, 2^{1561001016139} is an apocalyptic number.

1561001016139 is a deficient number, since it is larger than the sum of its proper divisors (1).

1561001016139 is an equidigital number, since it uses as much as digits as its factorization.

1561001016139 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4860, while the sum is 34.

The spelling of 1561001016139 in words is "one trillion, five hundred sixty-one billion, one million, sixteen thousand, one hundred thirty-nine".