72236421855 has 24 divisors (see below), whose sum is σ = 134841321888. Its totient is φ = 35562545856.

The previous prime is 72236421853. The next prime is 72236421937. The reversal of 72236421855 is 55812463227.

72236421855 is a `hidden beast` number, since 7 + 22 + 364 + 218 + 55 = 666.

It is not a de Polignac number, because 72236421855 - 2¹ = 72236421853 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 72236421855.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72236421853) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 61739947 + ... + 61741116.

It is an arithmetic number, because the mean of its divisors is an integer number (5618388412).

Almost surely, 2^72236421855 is an apocalyptic number.

72236421855 is a deficient number, since it is larger than the sum of its proper divisors (62604900033).

72236421855 is a wasteful number, since it uses less digits than its factorization.

72236421855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123481087 (or 123481084 counting only the distinct ones).

The product of its digits is 806400, while the sum is 45.

The spelling of 72236421855 in words is "seventy-two billion, two hundred thirty-six million, four hundred twenty-one thousand, eight hundred fifty-five".