1964866256640 has 1728 divisors, whose sum is σ = 8612718750720. Its totient is φ = 422032343040.

The previous prime is 1964866256627. The next prime is 1964866256677. The reversal of 1964866256640 is 466526684691.

1964866256640 is a `hidden beast` number, since 1 + 9 + 6 + 4 + 8 + 6 + 62 + 566 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1728).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 2375895907 + ... + 2375896733.

It is an arithmetic number, because the mean of its divisors is an integer number (4984212240).

Almost surely, 2^{1964866256640} is an apocalyptic number.

1964866256640 is a gapful number since it is divisible by the number (10) 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 1964866256640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4306359375360).

1964866256640 is an abundant number, since it is smaller than the sum of its proper divisors (6647852494080).

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

1964866256640 is a wasteful number, since it uses less digits than its factorization.

1964866256640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 955 (or 928 counting only the distinct ones).

The product of its (nonzero) digits is 89579520, while the sum is 63.

The spelling of 1964866256640 in words is "one trillion, nine hundred sixty-four billion, eight hundred sixty-six million, two hundred fifty-six thousand, six hundred forty".