161313431 has 2 divisors, whose sum is σ = 161313432. Its totient is φ = 161313430.

The previous prime is 161313409. The next prime is 161313437. The reversal of 161313431 is 134313161.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161313431 is a prime.

It is a super-2 number, since 2×161313431² = 52044046041983522, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 161313397 and 161313406.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161313437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80656715 + 80656716.

It is an arithmetic number, because the mean of its divisors is an integer number (80656716).

Almost surely, 2^161313431 is an apocalyptic number.

161313431 is a deficient number, since it is larger than the sum of its proper divisors (1).

161313431 is an equidigital number, since it uses as much as digits as its factorization.

161313431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 648, while the sum is 23.

The square root of 161313431 is about 12700.9224468146. The cubic root of 161313431 is about 544.3649770621.

Adding to 161313431 its reverse (134313161), we get a palindrome (295626592).

The spelling of 161313431 in words is "one hundred sixty-one million, three hundred thirteen thousand, four hundred thirty-one".