72185901745 has 4 divisors (see below), whose sum is σ = 86623082100. Its totient is φ = 57748721392.

The previous prime is 72185901719. The next prime is 72185901757. The reversal of 72185901745 is 54710958127.

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

It can be written as a sum of positive squares in 2 ways, for example, as 16089400336 + 56096501409 = 126844^2 + 236847^2 .

It is a cyclic number.

It is not a de Polignac number, because 72185901745 - 2¹⁹ = 72185377457 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7218590170 + ... + 7218590179.

It is an arithmetic number, because the mean of its divisors is an integer number (21655770525).

Almost surely, 2^72185901745 is an apocalyptic number.

It is an amenable number.

72185901745 is a deficient number, since it is larger than the sum of its proper divisors (14437180355).

72185901745 is a wasteful number, since it uses less digits than its factorization.

72185901745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14437180354.

The product of its (nonzero) digits is 705600, while the sum is 49.

The spelling of 72185901745 in words is "seventy-two billion, one hundred eighty-five million, nine hundred one thousand, seven hundred forty-five".