726636751 has 4 divisors (see below), whose sum is σ = 728292400. Its totient is φ = 724981104.

The previous prime is 726636749. The next prime is 726636787. The reversal of 726636751 is 157636627.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 157636627 = 61 ⋅2584207.

It is a cyclic number.

It is not a de Polignac number, because 726636751 - 2¹ = 726636749 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 726636698 and 726636707.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (726636721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 827166 + ... + 828043.

It is an arithmetic number, because the mean of its divisors is an integer number (182073100).

Almost surely, 2^726636751 is an apocalyptic number.

726636751 is a deficient number, since it is larger than the sum of its proper divisors (1655649).

726636751 is a wasteful number, since it uses less digits than its factorization.

726636751 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1655648.

The product of its digits is 317520, while the sum is 43.

The square root of 726636751 is about 26956.2006039427. The cubic root of 726636751 is about 899.0264167445.

The spelling of 726636751 in words is "seven hundred twenty-six million, six hundred thirty-six thousand, seven hundred fifty-one".