163631331 has 6 divisors (see below), whose sum is σ = 236356380. Its totient is φ = 109087548.

The previous prime is 163631327. The next prime is 163631359. The reversal of 163631331 is 133136361.

It is not a de Polignac number, because 163631331 - 2² = 163631327 is a prime.

It is a super-2 number, since 2×163631331² = 53550424969663122, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 163631295 and 163631304.

It is not an unprimeable number, because it can be changed into a prime (163631371) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9090621 + ... + 9090638.

It is an arithmetic number, because the mean of its divisors is an integer number (39392730).

Almost surely, 2^163631331 is an apocalyptic number.

163631331 is a deficient number, since it is larger than the sum of its proper divisors (72725049).

163631331 is a wasteful number, since it uses less digits than its factorization.

163631331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18181265 (or 18181262 counting only the distinct ones).

The product of its digits is 2916, while the sum is 27.

The square root of 163631331 is about 12791.8462701832. The cubic root of 163631331 is about 546.9599002273.

Adding to 163631331 its reverse (133136361), we get a palindrome (296767692).

The spelling of 163631331 in words is "one hundred sixty-three million, six hundred thirty-one thousand, three hundred thirty-one".