161443631 has 2 divisors, whose sum is σ = 161443632. Its totient is φ = 161443630.

The previous prime is 161443621. The next prime is 161443651. The reversal of 161443631 is 136344161.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 161443631 - 2¹⁰ = 161442607 is a prime.

It is a super-2 number, since 2×161443631² = 52128091980928322, which contains 22 as substring.

It is equal to p_9050861 and since 161443631 and 9050861 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 161443594 and 161443603.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161443621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80721815 + 80721816.

It is an arithmetic number, because the mean of its divisors is an integer number (80721816).

Almost surely, 2^161443631 is an apocalyptic number.

161443631 is a deficient number, since it is larger than the sum of its proper divisors (1).

161443631 is an equidigital number, since it uses as much as digits as its factorization.

161443631 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5184, while the sum is 29.

The square root of 161443631 is about 12706.0470249405. The cubic root of 161443631 is about 544.5113944216.

Adding to 161443631 its reverse (136344161), we get a palindrome (297787792).

The spelling of 161443631 in words is "one hundred sixty-one million, four hundred forty-three thousand, six hundred thirty-one".