161403831 has 12 divisors (see below), whose sum is σ = 246853152. Its totient is φ = 101272896.

The previous prime is 161403799. The next prime is 161403833. The reversal of 161403831 is 138304161.

It is not a de Polignac number, because 161403831 - 2⁵ = 161403799 is a prime.

It is a super-2 number, since 2×161403831² = 52102393322953122, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 161403795 and 161403804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161403833) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 527311 + ... + 527616.

It is an arithmetic number, because the mean of its divisors is an integer number (20571096).

Almost surely, 2^161403831 is an apocalyptic number.

161403831 is a deficient number, since it is larger than the sum of its proper divisors (85449321).

161403831 is a wasteful number, since it uses less digits than its factorization.

161403831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1054950 (or 1054947 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 161403831 is about 12704.4807449970. The cubic root of 161403831 is about 544.4666453979.

Adding to 161403831 its reverse (138304161), we get a palindrome (299707992).

The spelling of 161403831 in words is "one hundred sixty-one million, four hundred three thousand, eight hundred thirty-one".