1566666680 has 16 divisors (see below), whose sum is σ = 3525000120. Its totient is φ = 626666656.

The previous prime is 1566666649. The next prime is 1566666713. The reversal of 1566666680 is 866666651.

It is a congruent number.

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, 19583294 + ... + 19583373.

Almost surely, 2^1566666680 is an apocalyptic number.

1566666680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1566666680 is an abundant number, since it is smaller than the sum of its proper divisors (1958333440).

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

1566666680 is a wasteful number, since it uses less digits than its factorization.

1566666680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39166678 (or 39166674 counting only the distinct ones).

The product of its (nonzero) digits is 1866240, while the sum is 50.

The square root of 1566666680 is about 39581.1404585568. The cubic root of 1566666680 is about 1161.4277603821.

The spelling of 1566666680 in words is "one billion, five hundred sixty-six million, six hundred sixty-six thousand, six hundred eighty".