123999955 has 16 divisors (see below), whose sum is σ = 157813920. Its totient is φ = 93210112.

The previous prime is 123999929. The next prime is 123999971. The reversal of 123999955 is 559999321.

It is a cyclic number.

It is not a de Polignac number, because 123999955 - 2¹⁵ = 123967187 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 100281 + ... + 101509.

It is an arithmetic number, because the mean of its divisors is an integer number (9863370).

Almost surely, 2^123999955 is an apocalyptic number.

123999955 is a deficient number, since it is larger than the sum of its proper divisors (33813965).

123999955 is a wasteful number, since it uses less digits than its factorization.

123999955 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2438.

The product of its digits is 984150, while the sum is 52.

The square root of 123999955 is about 11135.5267051002. The cubic root of 123999955 is about 498.6630349017.

The spelling of 123999955 in words is "one hundred twenty-three million, nine hundred ninety-nine thousand, nine hundred fifty-five".