51591582 has 96 divisors (see below), whose sum is σ = 132986880. Its totient is φ = 14152320.

The previous prime is 51591581. The next prime is 51591587. The reversal of 51591582 is 28519515.

It is a happy number.

51591582 is a `hidden beast` number, since 515 + 91 + 58 + 2 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51591581) 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, 653019 + ... + 653097.

It is an arithmetic number, because the mean of its divisors is an integer number (1385280).

Almost surely, 2^51591582 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51591582, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (66493440).

51591582 is an abundant number, since it is smaller than the sum of its proper divisors (81395298).

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

51591582 is a wasteful number, since it uses less digits than its factorization.

51591582 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 238 (or 235 counting only the distinct ones).

The product of its digits is 18000, while the sum is 36.

The square root of 51591582 is about 7182.7280332754. The cubic root of 51591582 is about 372.2713507524.

The spelling of 51591582 in words is "fifty-one million, five hundred ninety-one thousand, five hundred eighty-two".