3936171220565 has 16 divisors (see below), whose sum is σ = 4931492754816. Its totient is φ = 3010363329600.

The previous prime is 3936171220543. The next prime is 3936171220567. The reversal of 3936171220565 is 5650221716393.

It is a happy number.

It is not a de Polignac number, because 3936171220565 - 2⁸ = 3936171220309 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 (3936171220567) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9241646 + ... + 9658175.

It is an arithmetic number, because the mean of its divisors is an integer number (308218297176).

Almost surely, 2^{3936171220565} is an apocalyptic number.

It is an amenable number.

3936171220565 is a deficient number, since it is larger than the sum of its proper divisors (995321534251).

3936171220565 is a wasteful number, since it uses less digits than its factorization.

3936171220565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18901660.

The product of its (nonzero) digits is 2041200, while the sum is 50.

The spelling of 3936171220565 in words is "three trillion, nine hundred thirty-six billion, one hundred seventy-one million, two hundred twenty thousand, five hundred sixty-five".