123620640 has 192 divisors, whose sum is σ = 457736832. Its totient is φ = 27648000.

The previous prime is 123620633. The next prime is 123620641. The reversal of 123620640 is 46026321.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 123620640.

It is not an unprimeable number, because it can be changed into a prime (123620641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 67740 + ... + 69540.

It is an arithmetic number, because the mean of its divisors is an integer number (2384046).

Almost surely, 2^123620640 is an apocalyptic number.

123620640 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 123620640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (228868416).

123620640 is an abundant number, since it is smaller than the sum of its proper divisors (334116192).

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

123620640 is a wasteful number, since it uses less digits than its factorization.

123620640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1843 (or 1835 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 123620640 is about 11118.4819107646. The cubic root of 123620640 is about 498.1540466326.

Adding to 123620640 its reverse (46026321), we get a palindrome (169646961).

The spelling of 123620640 in words is "one hundred twenty-three million, six hundred twenty thousand, six hundred forty".