72231660 has 36 divisors (see below), whose sum is σ = 219103248. Its totient is φ = 19261728.

The previous prime is 72231641. The next prime is 72231683. The reversal of 72231660 is 6613227.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 200464 + ... + 200823.

Almost surely, 2^72231660 is an apocalyptic number.

It is an amenable number.

72231660 is an abundant number, since it is smaller than the sum of its proper divisors (146871588).

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

72231660 is a wasteful number, since it uses less digits than its factorization.

72231660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 401302 (or 401297 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 27.

The square root of 72231660 is about 8498.9211079995. The cubic root of 72231660 is about 416.4624649181.

Adding to 72231660 its reverse (6613227), we get a palindrome (78844887).

The spelling of 72231660 in words is "seventy-two million, two hundred thirty-one thousand, six hundred sixty".