3945643567 has 4 divisors (see below), whose sum is σ = 3946037920. Its totient is φ = 3945249216.

The previous prime is 3945643547. The next prime is 3945643571. The reversal of 3945643567 is 7653465493.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7653465493 = 1747 ⋅4380919.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3945643567 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 (3945643547) 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, 181767 + ... + 202312.

It is an arithmetic number, because the mean of its divisors is an integer number (986509480).

Almost surely, 2^3945643567 is an apocalyptic number.

3945643567 is a deficient number, since it is larger than the sum of its proper divisors (394353).

3945643567 is a wasteful number, since it uses less digits than its factorization.

3945643567 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 394352.

The product of its digits is 8164800, while the sum is 52.

The square root of 3945643567 is about 62814.3579685409. The cubic root of 3945643567 is about 1580.1777782922.

The spelling of 3945643567 in words is "three billion, nine hundred forty-five million, six hundred forty-three thousand, five hundred sixty-seven".