1666636040 has 16 divisors (see below), whose sum is σ = 3749931180. Its totient is φ = 666654400.

The previous prime is 1666636031. The next prime is 1666636057. The reversal of 1666636040 is 406366661.

It can be written as a sum of positive squares in 2 ways, for example, as 1648197604 + 18438436 = 40598^2 + 4294^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1666635985 and 1666636003.

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, 20832911 + ... + 20832990.

Almost surely, 2^1666636040 is an apocalyptic number.

1666636040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1666636040 is an abundant number, since it is smaller than the sum of its proper divisors (2083295140).

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

1666636040 is a wasteful number, since it uses less digits than its factorization.

1666636040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41665912 (or 41665908 counting only the distinct ones).

The product of its (nonzero) digits is 93312, while the sum is 38.

The square root of 1666636040 is about 40824.4539461338. The cubic root of 1666636040 is about 1185.6238390665.

The spelling of 1666636040 in words is "one billion, six hundred sixty-six million, six hundred thirty-six thousand, forty".