163551331 has 4 divisors (see below), whose sum is σ = 165139312. Its totient is φ = 161963352.

The previous prime is 163551313. The next prime is 163551347. The reversal of 163551331 is 133155361.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 133155361 = 3109 ⋅42829.

It is a cyclic number.

It is not a de Polignac number, because 163551331 - 2⁵ = 163551299 is a prime.

It is a super-2 number, since 2×163551331² = 53498075743743122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 163551331.

It is not an unprimeable number, because it can be changed into a prime (163551301) 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, 793836 + ... + 794041.

It is an arithmetic number, because the mean of its divisors is an integer number (41284828).

Almost surely, 2^163551331 is an apocalyptic number.

163551331 is a deficient number, since it is larger than the sum of its proper divisors (1587981).

163551331 is a wasteful number, since it uses less digits than its factorization.

163551331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1587980.

The product of its digits is 4050, while the sum is 28.

The square root of 163551331 is about 12788.7188959645. The cubic root of 163551331 is about 546.8707487495.

The spelling of 163551331 in words is "one hundred sixty-three million, five hundred fifty-one thousand, three hundred thirty-one".