721370247 has 12 divisors (see below), whose sum is σ = 1041505704. Its totient is φ = 443919840.

The previous prime is 721370213. The next prime is 721370249. The reversal of 721370247 is 742073127.

It is not a de Polignac number, because 721370247 - 2⁸ = 721369991 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721370249) 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, 710904 + ... + 711917.

It is an arithmetic number, because the mean of its divisors is an integer number (86792142).

Almost surely, 2^721370247 is an apocalyptic number.

721370247 is a deficient number, since it is larger than the sum of its proper divisors (320135457).

721370247 is a wasteful number, since it uses less digits than its factorization.

721370247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1422850 (or 1422837 counting only the distinct ones).

The product of its (nonzero) digits is 16464, while the sum is 33.

The square root of 721370247 is about 26858.3366387422. The cubic root of 721370247 is about 896.8491659845.

The spelling of 721370247 in words is "seven hundred twenty-one million, three hundred seventy thousand, two hundred forty-seven".