661850486543 has 4 divisors (see below), whose sum is σ = 662010783840. Its totient is φ = 661690189248.

The previous prime is 661850486471. The next prime is 661850486573. The reversal of 661850486543 is 345684058166.

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 661850486543 - 2²⁰ = 661849437967 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661850486573) 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, 80142455 + ... + 80150712.

It is an arithmetic number, because the mean of its divisors is an integer number (165502695960).

Almost surely, 2^661850486543 is an apocalyptic number.

661850486543 is a deficient number, since it is larger than the sum of its proper divisors (160297297).

661850486543 is a wasteful number, since it uses less digits than its factorization.

661850486543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160297296.

The product of its (nonzero) digits is 16588800, while the sum is 56.

The spelling of 661850486543 in words is "six hundred sixty-one billion, eight hundred fifty million, four hundred eighty-six thousand, five hundred forty-three".