7811585442 has 48 divisors (see below), whose sum is σ = 17951333400. Its totient is φ = 2446503936.

The previous prime is 7811585417. The next prime is 7811585443. The reversal of 7811585442 is 2445851187.

It can be written as a sum of positive squares in 4 ways, for example, as 7791416361 + 20169081 = 88269^2 + 4491^2 .

It is a super-2 number, since 2×7811585442² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (7811585443) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 159934 + ... + 202982.

Almost surely, 2^7811585442 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7811585442, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8975666700).

7811585442 is an abundant number, since it is smaller than the sum of its proper divisors (10139747958).

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

7811585442 is a wasteful number, since it uses less digits than its factorization.

7811585442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43667 (or 43664 counting only the distinct ones).

The product of its digits is 358400, while the sum is 45.

The square root of 7811585442 is about 88383.1739755933. The cubic root of 7811585442 is about 1984.1738841877.

The spelling of 7811585442 in words is "seven billion, eight hundred eleven million, five hundred eighty-five thousand, four hundred forty-two".