1665866712 has 32 divisors (see below), whose sum is σ = 4191202800. Its totient is φ = 551750784.

The previous prime is 1665866677. The next prime is 1665866723. The reversal of 1665866712 is 2176685661.

1665866712 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×1665866712² = 5550223804299381888, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 217287 + ... + 224822.

Almost surely, 2^1665866712 is an apocalyptic number.

1665866712 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1665866712 is an abundant number, since it is smaller than the sum of its proper divisors (2525336088).

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

1665866712 is a wasteful number, since it uses less digits than its factorization.

1665866712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 442275 (or 442271 counting only the distinct ones).

The product of its digits is 725760, while the sum is 48.

The square root of 1665866712 is about 40815.0304667288. The cubic root of 1665866712 is about 1185.4413809134.

The spelling of 1665866712 in words is "one billion, six hundred sixty-five million, eight hundred sixty-six thousand, seven hundred twelve".