161100031 has 8 divisors (see below), whose sum is σ = 172454400. Its totient is φ = 150033240.

The previous prime is 161099989. The next prime is 161100061. The reversal of 161100031 is 130001161.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 161100031 - 2²³ = 152711423 is a prime.

It is a super-2 number, since 2×161100031² = 51906439976401922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 161099984 and 161100020.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161100061) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 70735 + ... + 72976.

It is an arithmetic number, because the mean of its divisors is an integer number (21556800).

Almost surely, 2^161100031 is an apocalyptic number.

161100031 is a deficient number, since it is larger than the sum of its proper divisors (11354369).

161100031 is a wasteful number, since it uses less digits than its factorization.

161100031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143789.

The product of its (nonzero) digits is 18, while the sum is 13.

The square root of 161100031 is about 12692.5187019756. The cubic root of 161100031 is about 544.1248260536.

Adding to 161100031 its reverse (130001161), we get a palindrome (291101192).

The spelling of 161100031 in words is "one hundred sixty-one million, one hundred thousand, thirty-one".