156742506694909 has 2 divisors, whose sum is σ = 156742506694910. Its totient is φ = 156742506694908.

The previous prime is 156742506694901. The next prime is 156742506695003. The reversal of 156742506694909 is 909496605247651.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 138331353259225 + 18411153435684 = 11761435^2 + 4290822^2 .

It is an emirp because it is prime and its reverse (909496605247651) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 156742506694909 - 2³ = 156742506694901 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (156742506694901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78371253347454 + 78371253347455.

It is an arithmetic number, because the mean of its divisors is an integer number (78371253347455).

Almost surely, 2^{156742506694909} is an apocalyptic number.

It is an amenable number.

156742506694909 is a deficient number, since it is larger than the sum of its proper divisors (1).

156742506694909 is an equidigital number, since it uses as much as digits as its factorization.

156742506694909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 881798400, while the sum is 73.

The spelling of 156742506694909 in words is "one hundred fifty-six trillion, seven hundred forty-two billion, five hundred six million, six hundred ninety-four thousand, nine hundred nine".