156261133340321 has 4 divisors (see below), whose sum is σ = 157694721719700. Its totient is φ = 154827544960944.

The previous prime is 156261133340309. The next prime is 156261133340357. The reversal of 156261133340321 is 123043331162651.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 136379888112400 + 19881245227921 = 11678180^2 + 4458839^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-156261133340321 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (156261133345321) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 716794189526 + ... + 716794189743.

It is an arithmetic number, because the mean of its divisors is an integer number (39423680429925).

Almost surely, 2^{156261133340321} is an apocalyptic number.

It is an amenable number.

156261133340321 is a deficient number, since it is larger than the sum of its proper divisors (1433588379379).

156261133340321 is a wasteful number, since it uses less digits than its factorization.

156261133340321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1433588379378.

The product of its (nonzero) digits is 233280, while the sum is 41.

The spelling of 156261133340321 in words is "one hundred fifty-six trillion, two hundred sixty-one billion, one hundred thirty-three million, three hundred forty thousand, three hundred twenty-one".