1666797378 has 32 divisors (see below), whose sum is σ = 3408894720. Its totient is φ = 543079680.

The previous prime is 1666797329. The next prime is 1666797383. The reversal of 1666797378 is 8737976661.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 245088 + ... + 251796.

It is an arithmetic number, because the mean of its divisors is an integer number (106527960).

Almost surely, 2^1666797378 is an apocalyptic number.

1666797378 is an abundant number, since it is smaller than the sum of its proper divisors (1742097342).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1666797378 is a wasteful number, since it uses less digits than its factorization.

1666797378 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7642.

The product of its digits is 16003008, while the sum is 60.

The square root of 1666797378 is about 40826.4298953509. The cubic root of 1666797378 is about 1185.6620957709.

The spelling of 1666797378 in words is "one billion, six hundred sixty-six million, seven hundred ninety-seven thousand, three hundred seventy-eight".