665250666 has 32 divisors (see below), whose sum is σ = 1422223488. Its totient is φ = 206933760.

The previous prime is 665250661. The next prime is 665250683. The reversal of 665250666 is 666052566.

It is a super-2 number, since 2×665250666² = 885116897226887112, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (665250661) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53131 + ... + 64446.

It is an arithmetic number, because the mean of its divisors is an integer number (44444484).

Almost surely, 2^665250666 is an apocalyptic number.

665250666 is an abundant number, since it is smaller than the sum of its proper divisors (756972822).

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

665250666 is a wasteful number, since it uses less digits than its factorization.

665250666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117646.

The product of its (nonzero) digits is 388800, while the sum is 42.

The square root of 665250666 is about 25792.4536638142. The cubic root of 665250666 is about 872.9615310638.

The spelling of 665250666 in words is "six hundred sixty-five million, two hundred fifty thousand, six hundred sixty-six".