3863866565 has 16 divisors (see below), whose sum is σ = 5000178288. Its totient is φ = 2849389056.

The previous prime is 3863866519. The next prime is 3863866571. The reversal of 3863866565 is 5656683683.

It can be written as a sum of positive squares in 8 ways, for example, as 508908481 + 3354958084 = 22559^2 + 57922^2 .

It is a cyclic number.

It is not a de Polignac number, because 3863866565 - 2⁸ = 3863866309 is a prime.

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 3863866565.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7097 + ... + 88193.

It is an arithmetic number, because the mean of its divisors is an integer number (312511143).

Almost surely, 2^3863866565 is an apocalyptic number.

It is an amenable number.

3863866565 is a deficient number, since it is larger than the sum of its proper divisors (1136311723).

3863866565 is a wasteful number, since it uses less digits than its factorization.

3863866565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81848.

The product of its digits is 18662400, while the sum is 56.

The square root of 3863866565 is about 62160.0077622260. The cubic root of 3863866565 is about 1569.1846097943.

It can be divided in two parts, 38638665 and 65, that multiplied together give a square (2511513225 = 50115²).

The spelling of 3863866565 in words is "three billion, eight hundred sixty-three million, eight hundred sixty-six thousand, five hundred sixty-five".