161261355236 has 24 divisors (see below), whose sum is σ = 283268018040. Its totient is φ = 80327826432.

The previous prime is 161261355217. The next prime is 161261355239. The reversal of 161261355236 is 632553162161.

It can be written as a sum of positive squares in 4 ways, for example, as 78349608100 + 82911747136 = 279910^2 + 287944^2 .

It is a super-3 number, since 3×161261355236³ (a number of 35 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 161261355193 and 161261355202.

It is not an unprimeable number, because it can be changed into a prime (161261355239) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3621620 + ... + 3665876.

It is an arithmetic number, because the mean of its divisors is an integer number (11802834085).

Almost surely, 2^161261355236 is an apocalyptic number.

It is an amenable number.

161261355236 is a deficient number, since it is larger than the sum of its proper divisors (122006662804).

161261355236 is a wasteful number, since it uses less digits than its factorization.

161261355236 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47663 (or 47661 counting only the distinct ones).

The product of its digits is 194400, while the sum is 41.

The spelling of 161261355236 in words is "one hundred sixty-one billion, two hundred sixty-one million, three hundred fifty-five thousand, two hundred thirty-six".