660606690 has 64 divisors (see below), whose sum is σ = 1675468800. Its totient is φ = 166355904.

The previous prime is 660606679. The next prime is 660606691. The reversal of 660606690 is 96606066.

It is a super-2 number, since 2×660606690² = 872802397745512200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (660606691) 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 31 ways as a sum of consecutive naturals, for example, 48451 + ... + 60569.

It is an arithmetic number, because the mean of its divisors is an integer number (26179200).

Almost surely, 2^660606690 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 660606690, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (837734400).

660606690 is an abundant number, since it is smaller than the sum of its proper divisors (1014862110).

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

660606690 is a wasteful number, since it uses less digits than its factorization.

660606690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12231.

The product of its (nonzero) digits is 69984, while the sum is 39.

The square root of 660606690 is about 25702.2701332003. The cubic root of 660606690 is about 870.9254651779.

The spelling of 660606690 in words is "six hundred sixty million, six hundred six thousand, six hundred ninety".