161555878258 has 8 divisors (see below), whose sum is σ = 242382957228. Its totient is φ = 80761559184.

The previous prime is 161555878213. The next prime is 161555878291. The reversal of 161555878258 is 852878555161.

It is a happy number.

161555878258 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 151778030569 + 9777847689 = 389587^2 + 98883^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×161555878258² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 161555878196 and 161555878205.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8177641 + ... + 8197372.

Almost surely, 2^161555878258 is an apocalyptic number.

161555878258 is a deficient number, since it is larger than the sum of its proper divisors (80827078970).

161555878258 is a wasteful number, since it uses less digits than its factorization.

161555878258 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16379948.

The product of its digits is 26880000, while the sum is 61.

The spelling of 161555878258 in words is "one hundred sixty-one billion, five hundred fifty-five million, eight hundred seventy-eight thousand, two hundred fifty-eight".