123666655 has 16 divisors (see below), whose sum is σ = 172477440. Its totient is φ = 83361312.

The previous prime is 123666637. The next prime is 123666659. The reversal of 123666655 is 556666321.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 123666655 - 2¹⁹ = 123142367 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123666659) 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, 27879 + ... + 32008.

It is an arithmetic number, because the mean of its divisors is an integer number (10779840).

Almost surely, 2^123666655 is an apocalyptic number.

123666655 is a deficient number, since it is larger than the sum of its proper divisors (48810785).

123666655 is an equidigital number, since it uses as much as digits as its factorization.

123666655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59958.

The product of its digits is 194400, while the sum is 40.

The square root of 123666655 is about 11120.5510205205. The cubic root of 123666655 is about 498.2158478412.

The spelling of 123666655 in words is "one hundred twenty-three million, six hundred sixty-six thousand, six hundred fifty-five".