123645220 has 12 divisors (see below), whose sum is σ = 259655004. Its totient is φ = 49458080.

The previous prime is 123645211. The next prime is 123645227. The reversal of 123645220 is 22546321.

It can be written as a sum of positive squares in 2 ways, for example, as 81577024 + 42068196 = 9032^2 + 6486^2 .

It is not an unprimeable number, because it can be changed into a prime (123645227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3091111 + ... + 3091150.

It is an arithmetic number, because the mean of its divisors is an integer number (21637917).

Almost surely, 2^123645220 is an apocalyptic number.

123645220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

123645220 is an abundant number, since it is smaller than the sum of its proper divisors (136009784).

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

123645220 is a wasteful number, since it uses less digits than its factorization.

123645220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6182270 (or 6182268 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 25.

The square root of 123645220 is about 11119.5872225546. The cubic root of 123645220 is about 498.1870611168.

The spelling of 123645220 in words is "one hundred twenty-three million, six hundred forty-five thousand, two hundred twenty".