161866383513 has 16 divisors (see below), whose sum is σ = 217452142080. Its totient is φ = 107096172416.

The previous prime is 161866383509. The next prime is 161866383521. The reversal of 161866383513 is 315383668161.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 161866383513 - 2² = 161866383509 is a prime.

It is a super-2 number, since 2×161866383513² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161866383583) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1648483 + ... + 1743911.

It is an arithmetic number, because the mean of its divisors is an integer number (13590758880).

Almost surely, 2^161866383513 is an apocalyptic number.

It is an amenable number.

161866383513 is a deficient number, since it is larger than the sum of its proper divisors (55585758567).

161866383513 is a wasteful number, since it uses less digits than its factorization.

161866383513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99696.

The product of its digits is 1866240, while the sum is 51.

The spelling of 161866383513 in words is "one hundred sixty-one billion, eight hundred sixty-six million, three hundred eighty-three thousand, five hundred thirteen".