123555979 has 4 divisors (see below), whose sum is σ = 127816560. Its totient is φ = 119295400.

The previous prime is 123555967. The next prime is 123555989. The reversal of 123555979 is 979555321.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 123555979 - 2⁵ = 123555947 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (123555959) 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, 2130247 + ... + 2130304.

It is an arithmetic number, because the mean of its divisors is an integer number (31954140).

Almost surely, 2^123555979 is an apocalyptic number.

123555979 is a deficient number, since it is larger than the sum of its proper divisors (4260581).

123555979 is an equidigital number, since it uses as much as digits as its factorization.

123555979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4260580.

The product of its digits is 425250, while the sum is 46.

The square root of 123555979 is about 11115.5737143883. The cubic root of 123555979 is about 498.0671766822.

The spelling of 123555979 in words is "one hundred twenty-three million, five hundred fifty-five thousand, nine hundred seventy-nine".