72224081 has 4 divisors (see below), whose sum is σ = 72539700. Its totient is φ = 71908464.

The previous prime is 72224059. The next prime is 72224137. The reversal of 72224081 is 18042227.

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

It can be written as a sum of positive squares in 2 ways, for example, as 38688400 + 33535681 = 6220^2 + 5791^2 .

It is a cyclic number.

It is not a de Polignac number, because 72224081 - 2¹⁰ = 72223057 is a prime.

It is a super-2 number, since 2×72224081² = 10432635752589122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 72224081.

It is not an unprimeable number, because it can be changed into a prime (72224051) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 157466 + ... + 157923.

It is an arithmetic number, because the mean of its divisors is an integer number (18134925).

Almost surely, 2^72224081 is an apocalyptic number.

It is an amenable number.

72224081 is a deficient number, since it is larger than the sum of its proper divisors (315619).

72224081 is a wasteful number, since it uses less digits than its factorization.

72224081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 315618.

The product of its (nonzero) digits is 1792, while the sum is 26.

The square root of 72224081 is about 8498.4752161785. The cubic root of 72224081 is about 416.4478984550.

The spelling of 72224081 in words is "seventy-two million, two hundred twenty-four thousand, eighty-one".