2091078640 has 80 divisors (see below), whose sum is σ = 5747935680. Its totient is φ = 692213760.

The previous prime is 2091078623. The next prime is 2091078707. The reversal of 2091078640 is 468701902.

It is a tau number, because it is divible by the number of its divisors (80).

It is a self number, because there is not a number n which added to its sum of digits gives 2091078640.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 48141 + ... + 80620.

It is an arithmetic number, because the mean of its divisors is an integer number (71849196).

Almost surely, 2^2091078640 is an apocalyptic number.

2091078640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2091078640 is an abundant number, since it is smaller than the sum of its proper divisors (3656857040).

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

2091078640 is a wasteful number, since it uses less digits than its factorization.

2091078640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128810 (or 128804 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 2091078640 is about 45728.3133299272. The cubic root of 2091078640 is about 1278.7631770273.

The spelling of 2091078640 in words is "two billion, ninety-one million, seventy-eight thousand, six hundred forty".