666620240 has 80 divisors (see below), whose sum is σ = 1820883456. Its totient is φ = 223756800.

The previous prime is 666620239. The next prime is 666620257. The reversal of 666620240 is 42026666.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 666620197 and 666620206.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17696 + ... + 40575.

Almost surely, 2^666620240 is an apocalyptic number.

It is an amenable number.

666620240 is an abundant number, since it is smaller than the sum of its proper divisors (1154263216).

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

666620240 is a wasteful number, since it uses less digits than its factorization.

666620240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58308 (or 58302 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 32.

The square root of 666620240 is about 25818.9899105290. The cubic root of 666620240 is about 873.5601855510.

The spelling of 666620240 in words is "six hundred sixty-six million, six hundred twenty thousand, two hundred forty".