726270661 has 2 divisors, whose sum is σ = 726270662. Its totient is φ = 726270660.

The previous prime is 726270659. The next prime is 726270689. The reversal of 726270661 is 166072627.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 590198436 + 136072225 = 24294^2 + 11665^2 .

It is a cyclic number.

It is not a de Polignac number, because 726270661 - 2¹ = 726270659 is a prime.

Together with 726270659, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 726270661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (726270631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 363135330 + 363135331.

It is an arithmetic number, because the mean of its divisors is an integer number (363135331).

Almost surely, 2^726270661 is an apocalyptic number.

It is an amenable number.

726270661 is a deficient number, since it is larger than the sum of its proper divisors (1).

726270661 is an equidigital number, since it uses as much as digits as its factorization.

726270661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 42336, while the sum is 37.

The square root of 726270661 is about 26949.4092885169. The cubic root of 726270661 is about 898.8754105879.

The spelling of 726270661 in words is "seven hundred twenty-six million, two hundred seventy thousand, six hundred sixty-one".