143172561 has 24 divisors (see below), whose sum is σ = 223841280. Its totient is φ = 81158112.

The previous prime is 143172553. The next prime is 143172571. The reversal of 143172561 is 165271341.

It is not a de Polignac number, because 143172561 - 2³ = 143172553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (143172541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14835 + ... + 22503.

It is an arithmetic number, because the mean of its divisors is an integer number (9326720).

Almost surely, 2^143172561 is an apocalyptic number.

It is an amenable number.

143172561 is a deficient number, since it is larger than the sum of its proper divisors (80668719).

143172561 is a wasteful number, since it uses less digits than its factorization.

143172561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7813 (or 7806 counting only the distinct ones).

The product of its digits is 5040, while the sum is 30.

The square root of 143172561 is about 11965.4737056249. The cubic root of 143172561 is about 523.1424129014.

The spelling of 143172561 in words is "one hundred forty-three million, one hundred seventy-two thousand, five hundred sixty-one".