3945643566 has 16 divisors (see below), whose sum is σ = 7948889424. Its totient is φ = 1305614144.

The previous prime is 3945643547. The next prime is 3945643571. The reversal of 3945643566 is 6653465493.

It is a Curzon number.

It is a congruent 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, 2399205 + ... + 2400848.

It is an arithmetic number, because the mean of its divisors is an integer number (496805589).

Almost surely, 2^3945643566 is an apocalyptic number.

3945643566 is an abundant number, since it is smaller than the sum of its proper divisors (4003245858).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3945643566 is a wasteful number, since it uses less digits than its factorization.

3945643566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4800195.

The product of its digits is 6998400, while the sum is 51.

The square root of 3945643566 is about 62814.3579605810. The cubic root of 3945643566 is about 1580.1777781587.

The spelling of 3945643566 in words is "three billion, nine hundred forty-five million, six hundred forty-three thousand, five hundred sixty-six".