3961544135640 has 384 divisors, whose sum is σ = 14720973488640. Its totient is φ = 835082846208.

The previous prime is 3961544135639. The next prime is 3961544135657. The reversal of 3961544135640 is 465314451693.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 163667779 + ... + 163691981.

It is an arithmetic number, because the mean of its divisors is an integer number (38335868460).

Almost surely, 2^{3961544135640} is an apocalyptic number.

3961544135640 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 3961544135640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7360486744320).

3961544135640 is an abundant number, since it is smaller than the sum of its proper divisors (10759429353000).

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

3961544135640 is a wasteful number, since it uses less digits than its factorization.

3961544135640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25403 (or 25386 counting only the distinct ones).

The product of its (nonzero) digits is 4665600, while the sum is 51.

The spelling of 3961544135640 in words is "three trillion, nine hundred sixty-one billion, five hundred forty-four million, one hundred thirty-five thousand, six hundred forty".