1666835243 has 4 divisors (see below), whose sum is σ = 1668518208. Its totient is φ = 1665152280.

The previous prime is 1666835239. The next prime is 1666835251. The reversal of 1666835243 is 3425386661.

It is a happy number.

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 1666835243 - 2² = 1666835239 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1666835194 and 1666835203.

It is not an unprimeable number, because it can be changed into a prime (1666835143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 839996 + ... + 841977.

It is an arithmetic number, because the mean of its divisors is an integer number (417129552).

Almost surely, 2^1666835243 is an apocalyptic number.

1666835243 is a deficient number, since it is larger than the sum of its proper divisors (1682965).

1666835243 is an equidigital number, since it uses as much as digits as its factorization.

1666835243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1682964.

The product of its digits is 622080, while the sum is 44.

The square root of 1666835243 is about 40826.8936241787. The cubic root of 1666835243 is about 1185.6710740178.

The spelling of 1666835243 in words is "one billion, six hundred sixty-six million, eight hundred thirty-five thousand, two hundred forty-three".