2091388445640 has 960 divisors, whose sum is σ = 7811093822400. Its totient is φ = 501506463744.

The previous prime is 2091388445639. The next prime is 2091388445681. The reversal of 2091388445640 is 465448831902.

2091388445640 is a `hidden beast` number, since 2 + 0 + 9 + 1 + 38 + 8 + 44 + 564 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 3998830419 + ... + 3998830941.

It is an arithmetic number, because the mean of its divisors is an integer number (8136556065).

Almost surely, 2^{2091388445640} is an apocalyptic number.

2091388445640 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 2091388445640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3905546911200).

2091388445640 is an abundant number, since it is smaller than the sum of its proper divisors (5719705376760).

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

2091388445640 is a wasteful number, since it uses less digits than its factorization.

2091388445640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 748 (or 722 counting only the distinct ones).

The product of its (nonzero) digits is 6635520, while the sum is 54.

The spelling of 2091388445640 in words is "two trillion, ninety-one billion, three hundred eighty-eight million, four hundred forty-five thousand, six hundred forty".