161231663 has 4 divisors (see below), whose sum is σ = 169717560. Its totient is φ = 152745768.

The previous prime is 161231659. The next prime is 161231683. The reversal of 161231663 is 366132161.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 161231663 - 2² = 161231659 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161231683) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4242920 + ... + 4242957.

It is an arithmetic number, because the mean of its divisors is an integer number (42429390).

Almost surely, 2^161231663 is an apocalyptic number.

161231663 is a deficient number, since it is larger than the sum of its proper divisors (8485897).

161231663 is an equidigital number, since it uses as much as digits as its factorization.

161231663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8485896.

The product of its digits is 3888, while the sum is 29.

The square root of 161231663 is about 12697.7030600026. The cubic root of 161231663 is about 544.2729839814.

The spelling of 161231663 in words is "one hundred sixty-one million, two hundred thirty-one thousand, six hundred sixty-three".