123240555 has 64 divisors (see below), whose sum is σ = 240768000. Its totient is φ = 59533056.

The previous prime is 123240539. The next prime is 123240569. The reversal of 123240555 is 555042321.

It is a happy number.

It is not a de Polignac number, because 123240555 - 2⁴ = 123240539 is a prime.

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

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 57951 + ... + 60039.

It is an arithmetic number, because the mean of its divisors is an integer number (3762000).

Almost surely, 2^123240555 is an apocalyptic number.

123240555 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

123240555 is a deficient number, since it is larger than the sum of its proper divisors (117527445).

123240555 is a wasteful number, since it uses less digits than its factorization.

123240555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2145 (or 2139 counting only the distinct ones).

The product of its (nonzero) digits is 6000, while the sum is 27.

The square root of 123240555 is about 11101.3762660312. The cubic root of 123240555 is about 497.6429797034.

Adding to 123240555 its reverse (555042321), we get a palindrome (678282876).

The spelling of 123240555 in words is "one hundred twenty-three million, two hundred forty thousand, five hundred fifty-five".