72205668 has 30 divisors (see below), whose sum is σ = 188760726. Its totient is φ = 24068448.

The previous prime is 72205649. The next prime is 72205669. The reversal of 72205668 is 86650227.

72205668 is a `hidden beast` number, since 72 + 20 + 566 + 8 = 666.

It can be written as a sum of positive squares in only one way, i.e., 61591104 + 10614564 = 7848^2 + 3258^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (72205669) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 111105 + ... + 111752.

Almost surely, 2^72205668 is an apocalyptic number.

It is an amenable number.

72205668 is an abundant number, since it is smaller than the sum of its proper divisors (116555058).

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

72205668 is a wasteful number, since it uses less digits than its factorization.

72205668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 222873 (or 222862 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The square root of 72205668 is about 8497.3918351457. The cubic root of 72205668 is about 416.4125053341.

The spelling of 72205668 in words is "seventy-two million, two hundred five thousand, six hundred sixty-eight".