123911640 has 192 divisors, whose sum is σ = 439869600. Its totient is φ = 31021056.

The previous prime is 123911639. The next prime is 123911651. The reversal of 123911640 is 46119321.

123911640 is a `hidden beast` number, since 1 + 2 + 3 + 9 + 11 + 640 = 666.

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 47 ways as a sum of consecutive naturals, for example, 311922 + ... + 312318.

Almost surely, 2^123911640 is an apocalyptic number.

123911640 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 123911640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (219934800).

123911640 is an abundant number, since it is smaller than the sum of its proper divisors (315957960).

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

123911640 is a wasteful number, since it uses less digits than its factorization.

123911640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 451 (or 424 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 123911640 is about 11131.5605374988. The cubic root of 123911640 is about 498.5446211886.

The spelling of 123911640 in words is "one hundred twenty-three million, nine hundred eleven thousand, six hundred forty".