661143043 has 4 divisors (see below), whose sum is σ = 721246968. Its totient is φ = 601039120.

The previous prime is 661143023. The next prime is 661143083. The reversal of 661143043 is 340341166.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 661143043 - 2⁵ = 661143011 is a prime.

It is a super-2 number, since 2×661143043² = 874220246614599698, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (661143013) 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, 30051946 + ... + 30051967.

It is an arithmetic number, because the mean of its divisors is an integer number (180311742).

Almost surely, 2^661143043 is an apocalyptic number.

661143043 is a deficient number, since it is larger than the sum of its proper divisors (60103925).

661143043 is a wasteful number, since it uses less digits than its factorization.

661143043 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60103924.

The product of its (nonzero) digits is 5184, while the sum is 28.

The square root of 661143043 is about 25712.7019778163. The cubic root of 661143043 is about 871.1611057032.

The spelling of 661143043 in words is "six hundred sixty-one million, one hundred forty-three thousand, forty-three".