1666666475 has 24 divisors (see below), whose sum is σ = 2083929120. Its totient is φ = 1322251520.

The previous prime is 1666666459. The next prime is 1666666481. The reversal of 1666666475 is 5746666661.

It is not a de Polignac number, because 1666666475 - 2⁴ = 1666666459 is a prime.

It is a hoax number, since the sum of its digits (53) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2090777 + ... + 2091573.

It is an arithmetic number, because the mean of its divisors is an integer number (86830380).

Almost surely, 2^1666666475 is an apocalyptic number.

1666666475 is a deficient number, since it is larger than the sum of its proper divisors (417262645).

1666666475 is a wasteful number, since it uses less digits than its factorization.

1666666475 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1399 (or 1394 counting only the distinct ones).

The product of its digits is 6531840, while the sum is 53.

The square root of 1666666475 is about 40824.8266989586. The cubic root of 1666666475 is about 1185.6310560475.

The spelling of 1666666475 in words is "one billion, six hundred sixty-six million, six hundred sixty-six thousand, four hundred seventy-five".