1666542794 has 8 divisors (see below), whose sum is σ = 2856930528. Its totient is φ = 714232620.

The previous prime is 1666542737. The next prime is 1666542821. The reversal of 1666542794 is 4972456661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 59519372 + ... + 59519399.

It is an arithmetic number, because the mean of its divisors is an integer number (357116316).

Almost surely, 2^1666542794 is an apocalyptic number.

1666542794 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

1666542794 is a deficient number, since it is larger than the sum of its proper divisors (1190387734).

1666542794 is a wasteful number, since it uses less digits than its factorization.

1666542794 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 119038780.

The product of its digits is 2177280, while the sum is 50.

The square root of 1666542794 is about 40823.3118940637. The cubic root of 1666542794 is about 1185.6017273117.

The spelling of 1666542794 in words is "one billion, six hundred sixty-six million, five hundred forty-two thousand, seven hundred ninety-four".