6440870261 has 8 divisors (see below), whose sum is σ = 7362685440. Its totient is φ = 5519477808.

The previous prime is 6440870231. The next prime is 6440870273. The reversal of 6440870261 is 1620780446.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6440870261 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6440870231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 72326 + ... + 134583.

It is an arithmetic number, because the mean of its divisors is an integer number (920335680).

Almost surely, 2^6440870261 is an apocalyptic number.

It is an amenable number.

6440870261 is a deficient number, since it is larger than the sum of its proper divisors (921815179).

6440870261 is a wasteful number, since it uses less digits than its factorization.

6440870261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 211363.

The product of its (nonzero) digits is 64512, while the sum is 38.

The square root of 6440870261 is about 80255.0326210139. The cubic root of 6440870261 is about 1860.5792951260.

The spelling of 6440870261 in words is "six billion, four hundred forty million, eight hundred seventy thousand, two hundred sixty-one".