721379457 has 12 divisors (see below), whose sum is σ = 1051215204. Its totient is φ = 476663040.

The previous prime is 721379447. The next prime is 721379497. The reversal of 721379457 is 754973127.

721379457 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 356416641 + 364962816 = 18879^2 + 19104^2 .

It is not a de Polignac number, because 721379457 - 2¹⁴ = 721363073 is a prime.

It is a super-3 number, since 3×721379457³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (721379447) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 353644 + ... + 355677.

It is an arithmetic number, because the mean of its divisors is an integer number (87601267).

Almost surely, 2^721379457 is an apocalyptic number.

It is an amenable number.

721379457 is a deficient number, since it is larger than the sum of its proper divisors (329835747).

721379457 is a wasteful number, since it uses less digits than its factorization.

721379457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 709440 (or 709437 counting only the distinct ones).

The product of its digits is 370440, while the sum is 45.

The square root of 721379457 is about 26858.5080933398. The cubic root of 721379457 is about 896.8529827696.

The spelling of 721379457 in words is "seven hundred twenty-one million, three hundred seventy-nine thousand, four hundred fifty-seven".