72105656 has 24 divisors (see below), whose sum is σ = 157272120. Its totient is φ = 30902256.

The previous prime is 72105643. The next prime is 72105689. The reversal of 72105656 is 65650127.

It is a happy number.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

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 5 ways as a sum of consecutive naturals, for example, 91580 + ... + 92363.

It is an arithmetic number, because the mean of its divisors is an integer number (6553005).

Almost surely, 2^72105656 is an apocalyptic number.

It is an amenable number.

72105656 is an abundant number, since it is smaller than the sum of its proper divisors (85166464).

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

72105656 is a wasteful number, since it uses less digits than its factorization.

72105656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183963 (or 183952 counting only the distinct ones).

The product of its (nonzero) digits is 12600, while the sum is 32.

The square root of 72105656 is about 8491.5049314006. The cubic root of 72105656 is about 416.2201589828.

The spelling of 72105656 in words is "seventy-two million, one hundred five thousand, six hundred fifty-six".