6442723081 has 4 divisors (see below), whose sum is σ = 6493453312. Its totient is φ = 6391992852.

The previous prime is 6442723009. The next prime is 6442723097. The reversal of 6442723081 is 1803272446.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1803272446 = 2 ⋅901636223.

It is a cyclic number.

It is not a de Polignac number, because 6442723081 - 2⁷ = 6442722953 is a prime.

It is a super-2 number, since 2×6442723081² = 83017361396900265122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6442723081.

It is not an unprimeable number, because it can be changed into a prime (6442723181) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25364925 + ... + 25365178.

It is an arithmetic number, because the mean of its divisors is an integer number (1623363328).

Almost surely, 2^6442723081 is an apocalyptic number.

It is an amenable number.

6442723081 is a deficient number, since it is larger than the sum of its proper divisors (50730231).

6442723081 is a wasteful number, since it uses less digits than its factorization.

6442723081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50730230.

The product of its (nonzero) digits is 64512, while the sum is 37.

The square root of 6442723081 is about 80266.5751169190. The cubic root of 6442723081 is about 1860.7576865484.

The spelling of 6442723081 in words is "six billion, four hundred forty-two million, seven hundred twenty-three thousand, eighty-one".