2191372064640 has 1024 divisors, whose sum is σ = 8771626598400. Its totient is φ = 512234496000.

The previous prime is 2191372064611. The next prime is 2191372064701. The reversal of 2191372064640 is 464602731912.

2191372064640 is a `hidden beast` number, since 219 + 1 + 372 + 0 + 6 + 4 + 64 + 0 = 666.

It is a super-2 number, since 2×2191372064640² (a number of 25 digits) contains 22 as substring.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 2256819355 + ... + 2256820325.

It is an arithmetic number, because the mean of its divisors is an integer number (8566041600).

Almost surely, 2^{2191372064640} is an apocalyptic number.

2191372064640 is a gapful number since it is divisible by the number (20) 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 2191372064640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4385813299200).

2191372064640 is an abundant number, since it is smaller than the sum of its proper divisors (6580254533760).

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

2191372064640 is a wasteful number, since it uses less digits than its factorization.

2191372064640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1424 (or 1406 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 45.

The spelling of 2191372064640 in words is "two trillion, one hundred ninety-one billion, three hundred seventy-two million, sixty-four thousand, six hundred forty".