661067143 has 4 divisors (see below), whose sum is σ = 721164168. Its totient is φ = 600970120.

The previous prime is 661067111. The next prime is 661067189. The reversal of 661067143 is 341760166.

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 661067143 - 2⁵ = 661067111 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 661067099 and 661067108.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661067443) 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, 30048496 + ... + 30048517.

It is an arithmetic number, because the mean of its divisors is an integer number (180291042).

Almost surely, 2^661067143 is an apocalyptic number.

661067143 is a deficient number, since it is larger than the sum of its proper divisors (60097025).

661067143 is a wasteful number, since it uses less digits than its factorization.

661067143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60097024.

The product of its (nonzero) digits is 18144, while the sum is 34.

The square root of 661067143 is about 25711.2260112193. The cubic root of 661067143 is about 871.1277676537.

The spelling of 661067143 in words is "six hundred sixty-one million, sixty-seven thousand, one hundred forty-three".