726783817945 has 4 divisors (see below), whose sum is σ = 872140581540. Its totient is φ = 581427054352.

The previous prime is 726783817919. The next prime is 726783817951. The reversal of 726783817945 is 549718387627.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 549718387627 = 8053 ⋅68262559.

It can be written as a sum of positive squares in 2 ways, for example, as 336988377049 + 389795440896 = 580507^2 + 624336^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-726783817945 is a prime.

It is a Smith number, since the sum of its digits (67) 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 polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 72678381790 + ... + 72678381799.

It is an arithmetic number, because the mean of its divisors is an integer number (218035145385).

Almost surely, 2^726783817945 is an apocalyptic number.

It is an amenable number.

726783817945 is a deficient number, since it is larger than the sum of its proper divisors (145356763595).

726783817945 is a wasteful number, since it uses less digits than its factorization.

726783817945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145356763594.

The product of its digits is 142248960, while the sum is 67.

The spelling of 726783817945 in words is "seven hundred twenty-six billion, seven hundred eighty-three million, eight hundred seventeen thousand, nine hundred forty-five".