1156520216161 has 4 divisors (see below), whose sum is σ = 1157661895572. Its totient is φ = 1155378536752.

The previous prime is 1156520216141. The next prime is 1156520216177. The reversal of 1156520216161 is 1616120256511.

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 151744527936 + 1004775688225 = 389544^2 + 1002385^2 .

It is a cyclic number.

It is not a de Polignac number, because 1156520216161 - 2⁹ = 1156520215649 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1156520216161.

It is not an unprimeable number, because it can be changed into a prime (1156520216101) 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, 570838186 + ... + 570840211.

It is an arithmetic number, because the mean of its divisors is an integer number (289415473893).

Almost surely, 2^{1156520216161} is an apocalyptic number.

It is an amenable number.

1156520216161 is a deficient number, since it is larger than the sum of its proper divisors (1141679411).

1156520216161 is a wasteful number, since it uses less digits than its factorization.

1156520216161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1141679410.

The product of its (nonzero) digits is 21600, while the sum is 37.

The spelling of 1156520216161 in words is "one trillion, one hundred fifty-six billion, five hundred twenty million, two hundred sixteen thousand, one hundred sixty-one".