726666 has 16 divisors (see below), whose sum is σ = 1461888. Its totient is φ = 240800.

The previous prime is 726659. The next prime is 726679. The reversal of 726666 is 666627.

726666 is a modest number, since divided by 6666 gives 72 as remainder.

It is an unprimeable number.

726666 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1471 + ... + 1901.

It is an arithmetic number, because the mean of its divisors is an integer number (91368).

2⁷²⁶⁶⁶⁶ is an apocalyptic number.

726666 is an abundant number, since it is smaller than the sum of its proper divisors (735222).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

726666 is a wasteful number, since it uses less digits than its factorization.

726666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 717.

The product of its digits is 18144, while the sum is 33.

The square root of 726666 is about 852.4470658053. The cubic root of 726666 is about 89.9038479292.

Adding to 726666 its product of digits (18144), we get a triangular number (744810 = T₁₂₂₀).

The spelling of 726666 in words is "seven hundred twenty-six thousand, six hundred sixty-six".