726989 has 2 divisors, whose sum is σ = 726990. Its totient is φ = 726988.

The previous prime is 726983. The next prime is 726991. The reversal of 726989 is 989627.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 722500 + 4489 = 850^2 + 67^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-726989 is a prime.

It is a super-2 number, since 2×726989² = 1057026012242, which contains 22 as substring.

Together with 726991, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 726989.

It is not a weakly prime, because it can be changed into another prime (726983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 363494 + 363495.

It is an arithmetic number, because the mean of its divisors is an integer number (363495).

2⁷²⁶⁹⁸⁹ is an apocalyptic number.

It is an amenable number.

726989 is a deficient number, since it is larger than the sum of its proper divisors (1).

726989 is an equidigital number, since it uses as much as digits as its factorization.

726989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54432, while the sum is 41.

The square root of 726989 is about 852.6364993360. The cubic root of 726989 is about 89.9171665842.

The spelling of 726989 in words is "seven hundred twenty-six thousand, nine hundred eighty-nine".