666502655 has 24 divisors (see below), whose sum is σ = 1001956032. Its totient is φ = 421872192.

The previous prime is 666502651. The next prime is 666502657. The reversal of 666502655 is 556205666.

It is not a de Polignac number, because 666502655 - 2² = 666502651 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666502651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 101447 + ... + 107816.

It is an arithmetic number, because the mean of its divisors is an integer number (41748168).

Almost surely, 2^666502655 is an apocalyptic number.

666502655 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

666502655 is a deficient number, since it is larger than the sum of its proper divisors (335453377).

666502655 is a wasteful number, since it uses less digits than its factorization.

666502655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209295 (or 209288 counting only the distinct ones).

The product of its (nonzero) digits is 324000, while the sum is 41.

The square root of 666502655 is about 25816.7127070818. The cubic root of 666502655 is about 873.5088201667.

The spelling of 666502655 in words is "six hundred sixty-six million, five hundred two thousand, six hundred fifty-five".