123619634640 has 240 divisors, whose sum is σ = 447666972480. Its totient is φ = 30468372480.

The previous prime is 123619634617. The next prime is 123619634647. The reversal of 123619634640 is 46436916321.

123619634640 is a `hidden beast` number, since 1 + 2 + 3 + 6 + 1 + 9 + 634 + 6 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

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 (123619634647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 450679 + ... + 671081.

It is an arithmetic number, because the mean of its divisors is an integer number (1865279052).

Almost surely, 2^123619634640 is an apocalyptic number.

123619634640 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 123619634640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (223833486240).

123619634640 is an abundant number, since it is smaller than the sum of its proper divisors (324047337840).

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

123619634640 is a wasteful number, since it uses less digits than its factorization.

123619634640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220482 (or 220473 counting only the distinct ones).

The product of its (nonzero) digits is 559872, while the sum is 45.

The spelling of 123619634640 in words is "one hundred twenty-three billion, six hundred nineteen million, six hundred thirty-four thousand, six hundred forty".