1581635386139 has 2 divisors, whose sum is σ = 1581635386140. Its totient is φ = 1581635386138.

The previous prime is 1581635386127. The next prime is 1581635386151. The reversal of 1581635386139 is 9316835361851.

It is a balanced prime because it is at equal distance from previous prime (1581635386127) and next prime (1581635386151).

It is an emirp because it is prime and its reverse (9316835361851) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1581635386139 is a prime.

It is not a weakly prime, because it can be changed into another prime (1581635386039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 790817693069 + 790817693070.

It is an arithmetic number, because the mean of its divisors is an integer number (790817693070).

Almost surely, 2^{1581635386139} is an apocalyptic number.

1581635386139 is a deficient number, since it is larger than the sum of its proper divisors (1).

1581635386139 is an equidigital number, since it uses as much as digits as its factorization.

1581635386139 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13996800, while the sum is 59.

The spelling of 1581635386139 in words is "one trillion, five hundred eighty-one billion, six hundred thirty-five million, three hundred eighty-six thousand, one hundred thirty-nine".