123320780820 has 72 divisors (see below), whose sum is σ = 378579985056. Its totient is φ = 32489326272.

The previous prime is 123320780819. The next prime is 123320780827. The reversal of 123320780820 is 28087023321.

It is a happy number.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123320780827) 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 23 ways as a sum of consecutive naturals, for example, 4112262 + ... + 4142141.

It is an arithmetic number, because the mean of its divisors is an integer number (5258055348).

Almost surely, 2^123320780820 is an apocalyptic number.

123320780820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

123320780820 is an abundant number, since it is smaller than the sum of its proper divisors (255259204236).

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

123320780820 is a wasteful number, since it uses less digits than its factorization.

123320780820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8254501 (or 8254496 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The spelling of 123320780820 in words is "one hundred twenty-three billion, three hundred twenty million, seven hundred eighty thousand, eight hundred twenty".