123782321520 has 960 divisors, whose sum is σ = 507903492096. Its totient is φ = 26615070720.

The previous prime is 123782321497. The next prime is 123782321539. The reversal of 123782321520 is 25123287321.

123782321520 is a `hidden beast` number, since 1 + 2 + 37 + 82 + 3 + 21 + 520 = 666.

It is a super-2 number, since 2×123782321520² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 323191249 + ... + 323191631.

Almost surely, 2^123782321520 is an apocalyptic number.

123782321520 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 123782321520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (253951746048).

123782321520 is an abundant number, since it is smaller than the sum of its proper divisors (384121170576).

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

123782321520 is a wasteful number, since it uses less digits than its factorization.

123782321520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 542 (or 533 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The spelling of 123782321520 in words is "one hundred twenty-three billion, seven hundred eighty-two million, three hundred twenty-one thousand, five hundred twenty".