123811904 has 56 divisors (see below), whose sum is σ = 267614400. Its totient is φ = 56609280.

The previous prime is 123811903. The next prime is 123811937. The reversal of 123811904 is 409118321.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is not an unprimeable number, because it can be changed into a prime (123811903) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33509 + ... + 37019.

Almost surely, 2^123811904 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 123811904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (133807200).

123811904 is an abundant number, since it is smaller than the sum of its proper divisors (143802496).

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

123811904 is a wasteful number, since it uses less digits than its factorization.

123811904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3571 (or 3561 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 123811904 is about 11127.0797606560. The cubic root of 123811904 is about 498.4108264058.

The spelling of 123811904 in words is "one hundred twenty-three million, eight hundred eleven thousand, nine hundred four".