6645255770 has 16 divisors (see below), whose sum is σ = 11962770120. Its totient is φ = 2657811264.

The previous prime is 6645255751. The next prime is 6645255797. The reversal of 6645255770 is 775525466.

It can be written as a sum of positive squares in 4 ways, for example, as 6251590489 + 393665281 = 79067^2 + 19841^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 76064 + ... + 138116.

Almost surely, 2^6645255770 is an apocalyptic number.

6645255770 is a deficient number, since it is larger than the sum of its proper divisors (5317514350).

6645255770 is a wasteful number, since it uses less digits than its factorization.

6645255770 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72769.

The product of its (nonzero) digits is 1764000, while the sum is 47.

The square root of 6645255770 is about 81518.4382210552. The cubic root of 6645255770 is about 1880.0550544086.

The spelling of 6645255770 in words is "six billion, six hundred forty-five million, two hundred fifty-five thousand, seven hundred seventy".