72381733321 has 2 divisors, whose sum is σ = 72381733322. Its totient is φ = 72381733320.

The previous prime is 72381733261. The next prime is 72381733339. The reversal of 72381733321 is 12333718327.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 48991395600 + 23390337721 = 221340^2 + 152939^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72381733321 is a prime.

It is not a weakly prime, because it can be changed into another prime (72381733381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36190866660 + 36190866661.

It is an arithmetic number, because the mean of its divisors is an integer number (36190866661).

Almost surely, 2^72381733321 is an apocalyptic number.

It is an amenable number.

72381733321 is a deficient number, since it is larger than the sum of its proper divisors (1).

72381733321 is an equidigital number, since it uses as much as digits as its factorization.

72381733321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 127008, while the sum is 40.

The spelling of 72381733321 in words is "seventy-two billion, three hundred eighty-one million, seven hundred thirty-three thousand, three hundred twenty-one".