123171840 has 352 divisors, whose sum is σ = 483419520. Its totient is φ = 29859840.

The previous prime is 123171827. The next prime is 123171859. The reversal of 123171840 is 48171321.

It is a tau number, because it is divible by the number of its divisors (352).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11197435 + ... + 11197445.

Almost surely, 2^123171840 is an apocalyptic number.

123171840 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 123171840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (241709760).

123171840 is an abundant number, since it is smaller than the sum of its proper divisors (360247680).

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

123171840 is an frugal number, since it uses more digits than its factorization.

123171840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57 (or 21 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 27.

The square root of 123171840 is about 11098.2809479667. The cubic root of 123171840 is about 497.5504725608.

The spelling of 123171840 in words is "one hundred twenty-three million, one hundred seventy-one thousand, eight hundred forty".