72205681 has 8 divisors (see below), whose sum is σ = 80477280. Its totient is φ = 64381248.

The previous prime is 72205673. The next prime is 72205697. The reversal of 72205681 is 18650227.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 72205681 - 2³ = 72205673 is a prime.

It is a super-2 number, since 2×72205681² = 10427320737347522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72205381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 111451 + ... + 112096.

It is an arithmetic number, because the mean of its divisors is an integer number (10059660).

Almost surely, 2^72205681 is an apocalyptic number.

It is an amenable number.

72205681 is a deficient number, since it is larger than the sum of its proper divisors (8271599).

72205681 is a wasteful number, since it uses less digits than its factorization.

72205681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 223583.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 72205681 is about 8497.3926000862. The cubic root of 72205681 is about 416.4125303246.

The spelling of 72205681 in words is "seventy-two million, two hundred five thousand, six hundred eighty-one".