3965552640 has 480 divisors, whose sum is σ = 16268091840. Its totient is φ = 905084928.

The previous prime is 3965552639. The next prime is 3965552671. The reversal of 3965552640 is 462555693.

3965552640 is a `hidden beast` number, since 3 + 96 + 5 + 552 + 6 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (480).

It is a super-2 number, since 2×3965552640² = 31451215481221939200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 5805739 + ... + 5806421.

It is an arithmetic number, because the mean of its divisors is an integer number (33891858).

Almost surely, 2^3965552640 is an apocalyptic number.

3965552640 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3965552640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8134045920).

3965552640 is an abundant number, since it is smaller than the sum of its proper divisors (12302539200).

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

3965552640 is an equidigital number, since it uses as much as digits as its factorization.

3965552640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 729 (or 700 counting only the distinct ones).

The product of its (nonzero) digits is 972000, while the sum is 45.

The square root of 3965552640 is about 62972.6340563899. The cubic root of 3965552640 is about 1582.8310935452.

The spelling of 3965552640 in words is "three billion, nine hundred sixty-five million, five hundred fifty-two thousand, six hundred forty".