3965561864 has 64 divisors (see below), whose sum is σ = 8271175680. Its totient is φ = 1767304000.

The previous prime is 3965561837. The next prime is 3965561893. The reversal of 3965561864 is 4681655693.

It is a happy number.

It is a super-2 number, since 2×3965561864² = 31451361794422308992, which contains 22 as substring.

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, 1191707 + ... + 1195029.

It is an arithmetic number, because the mean of its divisors is an integer number (129237120).

Almost surely, 2^3965561864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3965561864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4135587840).

3965561864 is an abundant number, since it is smaller than the sum of its proper divisors (4305613816).

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

3965561864 is a wasteful number, since it uses less digits than its factorization.

3965561864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3602 (or 3598 counting only the distinct ones).

The product of its digits is 4665600, while the sum is 53.

The square root of 3965561864 is about 62972.7072945097. The cubic root of 3965561864 is about 1582.8323207825.

The spelling of 3965561864 in words is "three billion, nine hundred sixty-five million, five hundred sixty-one thousand, eight hundred sixty-four".