660399770 has 16 divisors (see below), whose sum is σ = 1189284768. Its totient is φ = 264034320.

The previous prime is 660399763. The next prime is 660399797. The reversal of 660399770 is 77993066.

660399770 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×660399770² = 872255712432105800, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8105 + ... + 37235.

It is an arithmetic number, because the mean of its divisors is an integer number (74330298).

Almost surely, 2^660399770 is an apocalyptic number.

660399770 is a deficient number, since it is larger than the sum of its proper divisors (528884998).

660399770 is a wasteful number, since it uses less digits than its factorization.

660399770 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31405.

The product of its (nonzero) digits is 428652, while the sum is 47.

The square root of 660399770 is about 25698.2444925719. The cubic root of 660399770 is about 870.8345231600.

The spelling of 660399770 in words is "six hundred sixty million, three hundred ninety-nine thousand, seven hundred seventy".