721676 has 6 divisors (see below), whose sum is σ = 1262940. Its totient is φ = 360836.

The previous prime is 721663. The next prime is 721687. The reversal of 721676 is 676127.

It is an alternating number because its digits alternate between odd and even.

It is an unprimeable 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, 90206 + ... + 90213.

It is an arithmetic number, because the mean of its divisors is an integer number (210490).

2⁷²¹⁶⁷⁶ is an apocalyptic number.

It is an amenable number.

721676 is a deficient number, since it is larger than the sum of its proper divisors (541264).

721676 is a wasteful number, since it uses less digits than its factorization.

721676 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180423 (or 180421 counting only the distinct ones).

The product of its digits is 3528, while the sum is 29.

The square root of 721676 is about 849.5151558389. The cubic root of 721676 is about 89.6975858018.

The spelling of 721676 in words is "seven hundred twenty-one thousand, six hundred seventy-six".