721311403 has 12 divisors (see below), whose sum is σ = 759755880. Its totient is φ = 684587456.

The previous prime is 721311391. The next prime is 721311443. The reversal of 721311403 is 304113127.

It is not a de Polignac number, because 721311403 - 2¹³ = 721303211 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (721311443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 42351 + ... + 56887.

It is an arithmetic number, because the mean of its divisors is an integer number (63312990).

Almost surely, 2^721311403 is an apocalyptic number.

721311403 is a deficient number, since it is larger than the sum of its proper divisors (38444477).

721311403 is a wasteful number, since it uses less digits than its factorization.

721311403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14654 (or 14625 counting only the distinct ones).

The product of its (nonzero) digits is 504, while the sum is 22.

The square root of 721311403 is about 26857.2411650936. The cubic root of 721311403 is about 896.8247792346.

The spelling of 721311403 in words is "seven hundred twenty-one million, three hundred eleven thousand, four hundred three".