1578891640 has 64 divisors (see below), whose sum is σ = 3750883200. Its totient is φ = 596492928.

The previous prime is 1578891607. The next prime is 1578891641. The reversal of 1578891640 is 461988751.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1578891641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 260727 + ... + 266713.

It is an arithmetic number, because the mean of its divisors is an integer number (58607550).

Almost surely, 2^1578891640 is an apocalyptic number.

1578891640 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 1578891640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1875441600).

1578891640 is an abundant number, since it is smaller than the sum of its proper divisors (2171991560).

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

1578891640 is a wasteful number, since it uses less digits than its factorization.

1578891640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6364 (or 6360 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 49.

The square root of 1578891640 is about 39735.2694718433. The cubic root of 1578891640 is about 1164.4408744714.

The spelling of 1578891640 in words is "one billion, five hundred seventy-eight million, eight hundred ninety-one thousand, six hundred forty".