1666346938 has 4 divisors (see below), whose sum is σ = 2499520410. Its totient is φ = 833173468.

The previous prime is 1666346933. The next prime is 1666346947. The reversal of 1666346938 is 8396436661.

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

It can be written as a sum of positive squares in only one way, i.e., 1106693289 + 559653649 = 33267^2 + 23657^2 .

It is not an unprimeable number, because it can be changed into a prime (1666346933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 416586733 + ... + 416586736.

Almost surely, 2^1666346938 is an apocalyptic number.

1666346938 is a deficient number, since it is larger than the sum of its proper divisors (833173472).

1666346938 is an equidigital number, since it uses as much as digits as its factorization.

1666346938 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 833173471.

The product of its digits is 3359232, while the sum is 52.

The square root of 1666346938 is about 40820.9129981190. The cubic root of 1666346938 is about 1185.5552805978. Note that the first 3 decimals are identical.

The spelling of 1666346938 in words is "one billion, six hundred sixty-six million, three hundred forty-six thousand, nine hundred thirty-eight".