72320155 has 8 divisors (see below), whose sum is σ = 87883200. Its totient is φ = 57123456.

The previous prime is 72320153. The next prime is 72320167. The reversal of 72320155 is 55102327.

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 72320155 - 2¹ = 72320153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (72320153) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 91150 + ... + 91939.

It is an arithmetic number, because the mean of its divisors is an integer number (10985400).

Almost surely, 2^72320155 is an apocalyptic number.

72320155 is a deficient number, since it is larger than the sum of its proper divisors (15563045).

72320155 is a wasteful number, since it uses less digits than its factorization.

72320155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183173.

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

The square root of 72320155 is about 8504.1257634162. The cubic root of 72320155 is about 416.6324725717.

The spelling of 72320155 in words is "seventy-two million, three hundred twenty thousand, one hundred fifty-five".