72417806978785 has 4 divisors (see below), whose sum is σ = 86901368374548. Its totient is φ = 57934245583024.

The previous prime is 72417806978779. The next prime is 72417806978849. The reversal of 72417806978785 is 58787960871427.

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 46649350781089 + 25768456197696 = 6830033^2 + 5076264^2 .

It is a cyclic number.

It is not a de Polignac number, because 72417806978785 - 2¹¹ = 72417806976737 is a prime.

It is a super-2 number, since 2×72417806978785² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7241780697874 + ... + 7241780697883.

It is an arithmetic number, because the mean of its divisors is an integer number (21725342093637).

Almost surely, 2^{72417806978785} is an apocalyptic number.

It is an amenable number.

72417806978785 is a deficient number, since it is larger than the sum of its proper divisors (14483561395763).

72417806978785 is a wasteful number, since it uses less digits than its factorization.

72417806978785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14483561395762.

The product of its (nonzero) digits is 2655313920, while the sum is 79.

The spelling of 72417806978785 in words is "seventy-two trillion, four hundred seventeen billion, eight hundred six million, nine hundred seventy-eight thousand, seven hundred eighty-five".