72131806 has 4 divisors (see below), whose sum is σ = 108197712. Its totient is φ = 36065902.

The previous prime is 72131797. The next prime is 72131821. The reversal of 72131806 is 60813127.

It is a semiprime because it is the product of two primes.

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 as a sum of consecutive naturals, namely, 18032950 + ... + 18032953.

It is an arithmetic number, because the mean of its divisors is an integer number (27049428).

Almost surely, 2^72131806 is an apocalyptic number.

72131806 is a deficient number, since it is larger than the sum of its proper divisors (36065906).

72131806 is a wasteful number, since it uses less digits than its factorization.

72131806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36065905.

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 72131806 is about 8493.0445659963. The cubic root of 72131806 is about 416.2704686824.

The spelling of 72131806 in words is "seventy-two million, one hundred thirty-one thousand, eight hundred six".