123791640 has 192 divisors, whose sum is σ = 444463200. Its totient is φ = 27482112.

The previous prime is 123791609. The next prime is 123791641. The reversal of 123791640 is 46197321.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123791641) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 217276 + ... + 217844.

Almost surely, 2^123791640 is an apocalyptic number.

123791640 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 123791640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (222231600).

123791640 is an abundant number, since it is smaller than the sum of its proper divisors (320671560).

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

123791640 is a wasteful number, since it uses less digits than its factorization.

123791640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 634 (or 623 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 33.

The square root of 123791640 is about 11126.1691520487. The cubic root of 123791640 is about 498.3836336838.

The spelling of 123791640 in words is "one hundred twenty-three million, seven hundred ninety-one thousand, six hundred forty".