123881581440 has 320 divisors, whose sum is σ = 445658265360. Its totient is φ = 32792076288.

The previous prime is 123881581403. The next prime is 123881581441. The reversal of 123881581440 is 44185188321.

123881581440 is a `hidden beast` number, since 1 + 23 + 8 + 8 + 1 + 581 + 4 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (320).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123881581441) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 7093359 + ... + 7110801.

Almost surely, 2^123881581440 is an apocalyptic number.

123881581440 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 123881581440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (222829132680).

123881581440 is an abundant number, since it is smaller than the sum of its proper divisors (321776683920).

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

123881581440 is a wasteful number, since it uses less digits than its factorization.

123881581440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17611 (or 17590 counting only the distinct ones).

The product of its (nonzero) digits is 245760, while the sum is 45.

The spelling of 123881581440 in words is "one hundred twenty-three billion, eight hundred eighty-one million, five hundred eighty-one thousand, four hundred forty".