666287620 has 24 divisors (see below), whose sum is σ = 1401687000. Its totient is φ = 266042112.

The previous prime is 666287603. The next prime is 666287693. The reversal of 666287620 is 26782666.

It can be written as a sum of positive squares in 4 ways, for example, as 4460544 + 661827076 = 2112^2 + 25726^2 .

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, 17895 + ... + 40654.

It is an arithmetic number, because the mean of its divisors is an integer number (58403625).

Almost surely, 2^666287620 is an apocalyptic number.

It is an amenable number.

666287620 is an abundant number, since it is smaller than the sum of its proper divisors (735399380).

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

666287620 is a wasteful number, since it uses less digits than its factorization.

666287620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59127 (or 59125 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 43.

The square root of 666287620 is about 25812.5477239268. The cubic root of 666287620 is about 873.4148694666.

The spelling of 666287620 in words is "six hundred sixty-six million, two hundred eighty-seven thousand, six hundred twenty".