991726 has 8 divisors (see below), whose sum is σ = 1492920. Its totient is φ = 494088.

The previous prime is 991723. The next prime is 991733. The reversal of 991726 is 627199.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 991691 and 991700.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991723) 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, 21 + ... + 1408.

It is an arithmetic number, because the mean of its divisors is an integer number (186615).

2⁹⁹¹⁷²⁶ is an apocalyptic number.

991726 is a deficient number, since it is larger than the sum of its proper divisors (501194).

991726 is a wasteful number, since it uses less digits than its factorization.

991726 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1778.

The product of its digits is 6804, while the sum is 34.

The square root of 991726 is about 995.8544070295. The cubic root of 991726 is about 99.7234358277.

The spelling of 991726 in words is "nine hundred ninety-one thousand, seven hundred twenty-six".