1666801923 has 16 divisors (see below), whose sum is σ = 2344417920. Its totient is φ = 1050446016.

The previous prime is 1666801909. The next prime is 1666801931. The reversal of 1666801923 is 3291086661.

It is not a de Polignac number, because 1666801923 - 2¹⁴ = 1666785539 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1666801943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4690 + ... + 57927.

It is an arithmetic number, because the mean of its divisors is an integer number (146526120).

Almost surely, 2^1666801923 is an apocalyptic number.

1666801923 is a deficient number, since it is larger than the sum of its proper divisors (677615997).

1666801923 is a wasteful number, since it uses less digits than its factorization.

1666801923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63106.

The product of its (nonzero) digits is 93312, while the sum is 42.

The square root of 1666801923 is about 40826.4855577847. The cubic root of 1666801923 is about 1185.6631734522.

The spelling of 1666801923 in words is "one billion, six hundred sixty-six million, eight hundred one thousand, nine hundred twenty-three".