123115545 has 40 divisors (see below), whose sum is σ = 252229824. Its totient is φ = 56280096.

The previous prime is 123115543. The next prime is 123115561. The reversal of 123115545 is 545511321.

123115545 is a `hidden beast` number, since 1 + 2 + 3 + 115 + 545 = 666.

It is not a de Polignac number, because 123115545 - 2¹ = 123115543 is a prime.

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (123115543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 18879 + ... + 24548.

Almost surely, 2^123115545 is an apocalyptic number.

123115545 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

123115545 is an abundant number, since it is smaller than the sum of its proper divisors (129114279).

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

123115545 is an equidigital number, since it uses as much as digits as its factorization.

123115545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43451 (or 43442 counting only the distinct ones).

The product of its digits is 3000, while the sum is 27.

The square root of 123115545 is about 11095.7444545195. The cubic root of 123115545 is about 497.4746601236.

Adding to 123115545 its reverse (545511321), we get a palindrome (668626866).

The spelling of 123115545 in words is "one hundred twenty-three million, one hundred fifteen thousand, five hundred forty-five".