2591432640 has 336 divisors, whose sum is σ = 9296265888. Its totient is φ = 662003712.

The previous prime is 2591432573. The next prime is 2591432647. The reversal of 2591432640 is 462341952.

It is a happy number.

2591432640 is a `hidden beast` number, since 2 + 5 + 9 + 1 + 4 + 3 + 2 + 640 = 666.

2591432640 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 2591432595 and 2591432604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2591432647) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 8844334 + ... + 8844626.

It is an arithmetic number, because the mean of its divisors is an integer number (27667458).

Almost surely, 2^2591432640 is an apocalyptic number.

2591432640 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 2591432640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4648132944).

2591432640 is an abundant number, since it is smaller than the sum of its proper divisors (6704833248).

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

2591432640 is a wasteful number, since it uses less digits than its factorization.

2591432640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 436 (or 423 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The square root of 2591432640 is about 50906.1159390500. The cubic root of 2591432640 is about 1373.5568576589.

The spelling of 2591432640 in words is "two billion, five hundred ninety-one million, four hundred thirty-two thousand, six hundred forty".