123771649536 has 560 divisors, whose sum is σ = 403603453440. Its totient is φ = 37757767680.

The previous prime is 123771649523. The next prime is 123771649537. The reversal of 123771649536 is 635946177321.

123771649536 is a `hidden beast` number, since 1 + 2 + 37 + 71 + 6 + 4 + 9 + 536 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123771649537) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 219842791 + ... + 219843353.

Almost surely, 2^123771649536 is an apocalyptic number.

123771649536 is a gapful number since it is divisible by the number (16) 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 123771649536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (201801726720).

123771649536 is an abundant number, since it is smaller than the sum of its proper divisors (279831803904).

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

123771649536 is an frugal number, since it uses more digits than its factorization.

123771649536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 649 (or 618 counting only the distinct ones).

The product of its digits is 5715360, while the sum is 54.

The spelling of 123771649536 in words is "one hundred twenty-three billion, seven hundred seventy-one million, six hundred forty-nine thousand, five hundred thirty-six".