666522155 has 16 divisors (see below), whose sum is σ = 863442720. Its totient is φ = 491006208.

The previous prime is 666522113. The next prime is 666522163. The reversal of 666522155 is 551225666.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 666522155 - 2¹⁰ = 666521131 is a prime.

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, 14999 + ... + 39471.

It is an arithmetic number, because the mean of its divisors is an integer number (53965170).

Almost surely, 2^666522155 is an apocalyptic number.

666522155 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

666522155 is a deficient number, since it is larger than the sum of its proper divisors (196920565).

666522155 is a wasteful number, since it uses less digits than its factorization.

666522155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24910.

The product of its digits is 108000, while the sum is 38.

The square root of 666522155 is about 25817.0903666544. The cubic root of 666522155 is about 873.5173388904.

The spelling of 666522155 in words is "six hundred sixty-six million, five hundred twenty-two thousand, one hundred fifty-five".