161432431 has 2 divisors, whose sum is σ = 161432432. Its totient is φ = 161432430.

The previous prime is 161432389. The next prime is 161432477. The reversal of 161432431 is 134234161.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 161432431 - 2²³ = 153043823 is a prime.

It is a super-2 number, since 2×161432431² = 52120859557139522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 161432396 and 161432405.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161432231) 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 as a sum of consecutive naturals, namely, 80716215 + 80716216.

It is an arithmetic number, because the mean of its divisors is an integer number (80716216).

Almost surely, 2^161432431 is an apocalyptic number.

161432431 is a deficient number, since it is larger than the sum of its proper divisors (1).

161432431 is an equidigital number, since it uses as much as digits as its factorization.

161432431 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1728, while the sum is 25.

The square root of 161432431 is about 12705.6062822677. The cubic root of 161432431 is about 544.4988024752.

Adding to 161432431 its reverse (134234161), we get a palindrome (295666592).

The spelling of 161432431 in words is "one hundred sixty-one million, four hundred thirty-two thousand, four hundred thirty-one".