723691 has 8 divisors (see below), whose sum is σ = 781200. Its totient is φ = 668160.

The previous prime is 723661. The next prime is 723721. The reversal of 723691 is 196327.

723691 = T₁₃₀ + T₁₃₁ + ... + T₁₈₆.

It is an interprime number because it is at equal distance from previous prime (723661) and next prime (723721).

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

It is a cyclic number.

It is not a de Polignac number, because 723691 - 2⁷ = 723563 is a prime.

It is a Duffinian number.

723691 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (723601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 315 + ... + 1243.

It is an arithmetic number, because the mean of its divisors is an integer number (97650).

2⁷²³⁶⁹¹ is an apocalyptic number.

723691 is a deficient number, since it is larger than the sum of its proper divisors (57509).

723691 is a wasteful number, since it uses less digits than its factorization.

723691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 989.

The product of its digits is 2268, while the sum is 28.

The square root of 723691 is about 850.7002997531. The cubic root of 723691 is about 89.7809901180.

The spelling of 723691 in words is "seven hundred twenty-three thousand, six hundred ninety-one".