72820318 has 4 divisors (see below), whose sum is σ = 109230480. Its totient is φ = 36410158.

The previous prime is 72820313. The next prime is 72820327. The reversal of 72820318 is 81302827.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×72820318² = 10605597427242248, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 72820318.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72820313) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18205078 + ... + 18205081.

It is an arithmetic number, because the mean of its divisors is an integer number (27307620).

Almost surely, 2^72820318 is an apocalyptic number.

72820318 is a deficient number, since it is larger than the sum of its proper divisors (36410162).

72820318 is a wasteful number, since it uses less digits than its factorization.

72820318 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36410161.

The product of its (nonzero) digits is 5376, while the sum is 31.

The square root of 72820318 is about 8533.4821731811. The cubic root of 72820318 is about 417.5907374464.

The spelling of 72820318 in words is "seventy-two million, eight hundred twenty thousand, three hundred eighteen".