72938321820 has 432 divisors, whose sum is σ = 277884105408. Its totient is φ = 15349340160.

The previous prime is 72938321761. The next prime is 72938321831. The reversal of 72938321820 is 2812383927.

It is a super-2 number, since 2×72938321820² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 70744705 + ... + 70745735.

It is an arithmetic number, because the mean of its divisors is an integer number (643250244).

Almost surely, 2^72938321820 is an apocalyptic number.

72938321820 is a gapful number since it is divisible by the number (70) 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 72938321820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (138942052704).

72938321820 is an abundant number, since it is smaller than the sum of its proper divisors (204945783588).

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

72938321820 is a wasteful number, since it uses less digits than its factorization.

72938321820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1690 (or 1678 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 45.

The spelling of 72938321820 in words is "seventy-two billion, nine hundred thirty-eight million, three hundred twenty-one thousand, eight hundred twenty".