723986 has 4 divisors (see below), whose sum is σ = 1085982. Its totient is φ = 361992.

The previous prime is 723977. The next prime is 723997. The reversal of 723986 is 689327.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 689327 = 163 ⋅4229.

It can be written as a sum of positive squares in only one way, i.e., 516961 + 207025 = 719^2 + 455^2 .

It is a Curzon number.

It is an unprimeable number.

723986 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 180995 + ... + 180998.

2⁷²³⁹⁸⁶ is an apocalyptic number.

723986 is a deficient number, since it is larger than the sum of its proper divisors (361996).

723986 is a wasteful number, since it uses less digits than its factorization.

723986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 361995.

The product of its digits is 18144, while the sum is 35.

The square root of 723986 is about 850.8736686489. The cubic root of 723986 is about 89.7931876784.

The spelling of 723986 in words is "seven hundred twenty-three thousand, nine hundred eighty-six".