1666293820 has 48 divisors (see below), whose sum is σ = 3597955200. Its totient is φ = 647903744.

The previous prime is 1666293793. The next prime is 1666293821. The reversal of 1666293820 is 283926661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666293821) 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, 134112 + ... + 146008.

It is an arithmetic number, because the mean of its divisors is an integer number (74957400).

Almost surely, 2^1666293820 is an apocalyptic number.

1666293820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1666293820 is an abundant number, since it is smaller than the sum of its proper divisors (1931661380).

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

1666293820 is a wasteful number, since it uses less digits than its factorization.

1666293820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12102 (or 12100 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 43.

The square root of 1666293820 is about 40820.2623705434. The cubic root of 1666293820 is about 1185.5426831822.

The spelling of 1666293820 in words is "one billion, six hundred sixty-six million, two hundred ninety-three thousand, eight hundred twenty".