726365661 has 12 divisors (see below), whose sum is σ = 1126608192. Its totient is φ = 415066008.

The previous prime is 726365657. The next prime is 726365663. The reversal of 726365661 is 166563627.

It is not a de Polignac number, because 726365661 - 2² = 726365657 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (726365663) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 2470485 + ... + 2470778.

It is an arithmetic number, because the mean of its divisors is an integer number (93884016).

Almost surely, 2^726365661 is an apocalyptic number.

It is an amenable number.

726365661 is a deficient number, since it is larger than the sum of its proper divisors (400242531).

726365661 is a wasteful number, since it uses less digits than its factorization.

726365661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4941280 (or 4941273 counting only the distinct ones).

The product of its digits is 272160, while the sum is 42.

The square root of 726365661 is about 26951.1717927069. The cubic root of 726365661 is about 898.9146014138.

The spelling of 726365661 in words is "seven hundred twenty-six million, three hundred sixty-five thousand, six hundred sixty-one".