721094721 has 16 divisors (see below), whose sum is σ = 973681344. Its totient is φ = 474649344.

The previous prime is 721094719. The next prime is 721094741. The reversal of 721094721 is 127490127.

It is not a de Polignac number, because 721094721 - 2¹ = 721094719 is a prime.

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

It is not an unprimeable number, because it can be changed into a prime (721094741) 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, 96885 + ... + 104061.

It is an arithmetic number, because the mean of its divisors is an integer number (60855084).

Almost surely, 2^721094721 is an apocalyptic number.

721094721 is the 14354-th nonagonal number.

It is an amenable number.

721094721 is a deficient number, since it is larger than the sum of its proper divisors (252586623).

721094721 is a wasteful number, since it uses less digits than its factorization.

721094721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7600.

The product of its (nonzero) digits is 7056, while the sum is 33.

The square root of 721094721 is about 26853.2069034594. The cubic root of 721094721 is about 896.7349681637.

The spelling of 721094721 in words is "seven hundred twenty-one million, ninety-four thousand, seven hundred twenty-one".