72205531 has 8 divisors (see below), whose sum is σ = 73037520. Its totient is φ = 71377152.

The previous prime is 72205513. The next prime is 72205547. The reversal of 72205531 is 13550227.

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 72205531 - 2⁵ = 72205499 is a prime.

It is a super-2 number, since 2×72205531² = 10427277413983922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 72205496 and 72205505.

It is not an unprimeable number, because it can be changed into a prime (72205501) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 63736 + ... + 64858.

It is an arithmetic number, because the mean of its divisors is an integer number (9129690).

Almost surely, 2^72205531 is an apocalyptic number.

72205531 is a deficient number, since it is larger than the sum of its proper divisors (831989).

72205531 is a wasteful number, since it uses less digits than its factorization.

72205531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1805.

The product of its (nonzero) digits is 2100, while the sum is 25.

The square root of 72205531 is about 8497.3837738447. The cubic root of 72205531 is about 416.4122419728.

Adding to 72205531 its reverse (13550227), we get a palindrome (85755758).

The spelling of 72205531 in words is "seventy-two million, two hundred five thousand, five hundred thirty-one".