123811840 has 96 divisors (see below), whose sum is σ = 302505840. Its totient is φ = 48627712.

The previous prime is 123811837. The next prime is 123811843. The reversal of 123811840 is 48118321.

It is an interprime number because it is at equal distance from previous prime (123811837) and next prime (123811843).

It is a junction number, because it is equal to n+sod(n) for n = 123811799 and 123811808.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123811843) 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, 1095624 + ... + 1095736.

Almost surely, 2^123811840 is an apocalyptic number.

123811840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 123811840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (151252920).

123811840 is an abundant number, since it is smaller than the sum of its proper divisors (178694000).

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

123811840 is a wasteful number, since it uses less digits than its factorization.

123811840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 247 (or 227 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 28.

The square root of 123811840 is about 11127.0768847887. The cubic root of 123811840 is about 498.4107405274.

The spelling of 123811840 in words is "one hundred twenty-three million, eight hundred eleven thousand, eight hundred forty".