721867849 has 16 divisors (see below), whose sum is σ = 745758720. Its totient is φ = 698472720.

The previous prime is 721867841. The next prime is 721867859. The reversal of 721867849 is 948768127.

It is a cyclic number.

It is not a de Polignac number, because 721867849 - 2³ = 721867841 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 721867796 and 721867805.

It is not an unprimeable number, because it can be changed into a prime (721867841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1506792 + ... + 1507270.

It is an arithmetic number, because the mean of its divisors is an integer number (46609920).

Almost surely, 2^721867849 is an apocalyptic number.

It is an amenable number.

721867849 is a deficient number, since it is larger than the sum of its proper divisors (23890871).

721867849 is a wasteful number, since it uses less digits than its factorization.

721867849 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 900.

The product of its digits is 1354752, while the sum is 52.

The square root of 721867849 is about 26867.5984970745. The cubic root of 721867849 is about 897.0553344379.

The spelling of 721867849 in words is "seven hundred twenty-one million, eight hundred sixty-seven thousand, eight hundred forty-nine".