123655221 has 32 divisors (see below), whose sum is σ = 192796800. Its totient is φ = 78226560.

The previous prime is 123655219. The next prime is 123655243. The reversal of 123655221 is 122556321.

It is a happy number.

123655221 is a `hidden beast` number, since 1 + 2 + 3 + 655 + 2 + 2 + 1 = 666.

It is not a de Polignac number, because 123655221 - 2¹ = 123655219 is a prime.

It is a super-2 number, since 2×123655221² = 30581227361117682, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123655271) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 39450 + ... + 42468.

It is an arithmetic number, because the mean of its divisors is an integer number (6024900).

Almost surely, 2^123655221 is an apocalyptic number.

It is an amenable number.

123655221 is a deficient number, since it is larger than the sum of its proper divisors (69141579).

123655221 is a wasteful number, since it uses less digits than its factorization.

123655221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3106 (or 3100 counting only the distinct ones).

The product of its digits is 3600, while the sum is 27.

The square root of 123655221 is about 11120.0369154064. The cubic root of 123655221 is about 498.2004926495.

The spelling of 123655221 in words is "one hundred twenty-three million, six hundred fifty-five thousand, two hundred twenty-one".