163981431 has 6 divisors (see below), whose sum is σ = 236862080. Its totient is φ = 109320948.

The previous prime is 163981409. The next prime is 163981451. The reversal of 163981431 is 134189361.

163981431 is a `hidden beast` number, since 1 + 639 + 8 + 14 + 3 + 1 = 666.

163981431 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 163981431 - 2¹⁰ = 163980407 is a prime.

It is a super-2 number, since 2×163981431² = 53779819425615522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (163981451) 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, 9110071 + ... + 9110088.

Almost surely, 2^163981431 is an apocalyptic number.

163981431 is a deficient number, since it is larger than the sum of its proper divisors (72880649).

163981431 is a wasteful number, since it uses less digits than its factorization.

163981431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18220165 (or 18220162 counting only the distinct ones).

The product of its digits is 15552, while the sum is 36.

The square root of 163981431 is about 12805.5234566963. The cubic root of 163981431 is about 547.3497079189.

The spelling of 163981431 in words is "one hundred sixty-three million, nine hundred eighty-one thousand, four hundred thirty-one".