72021312 has 168 divisors, whose sum is σ = 234098592. Its totient is φ = 21772800.

The previous prime is 72021283. The next prime is 72021331. The reversal of 72021312 is 21312027.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 170862 + ... + 171282.

It is an arithmetic number, because the mean of its divisors is an integer number (1393444).

Almost surely, 2^72021312 is an apocalyptic number.

72021312 is a gapful number since it is divisible by the number (72) 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 72021312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117049296).

72021312 is an abundant number, since it is smaller than the sum of its proper divisors (162077280).

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

72021312 is a wasteful number, since it uses less digits than its factorization.

72021312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 459 (or 437 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 18.

The square root of 72021312 is about 8486.5371029649. The cubic root of 72021312 is about 416.0578075485.

Adding to 72021312 its reverse (21312027), we get a palindrome (93333339).

The spelling of 72021312 in words is "seventy-two million, twenty-one thousand, three hundred twelve".