6402720289 has 45 divisors (see below), whose sum is σ = 7919796689. Its totient is φ = 5175499560.

The previous prime is 6402720287. The next prime is 6402720293. The reversal of 6402720289 is 9820272046.

The square root of 6402720289 is 80017.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 6402720289 - 2¹ = 6402720287 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6402720287) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 90179124 + ... + 90179194.

Almost surely, 2^6402720289 is an apocalyptic number.

6402720289 is the 80017-th square number.

6402720289 is the 40009-th centered octagonal number.

It is an amenable number.

6402720289 is a deficient number, since it is larger than the sum of its proper divisors (1517076400).

6402720289 is an frugal number, since it uses more digits than its factorization.

6402720289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 216 (or 101 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 40.

The cubic root of 6402720289 is about 1856.8985474978.

The spelling of 6402720289 in words is "six billion, four hundred two million, seven hundred twenty thousand, two hundred eighty-nine".