51185442 has 64 divisors (see below), whose sum is σ = 133208064. Its totient is φ = 12714240.

The previous prime is 51185441. The next prime is 51185479. The reversal of 51185442 is 24458115.

It is not an unprimeable number, because it can be changed into a prime (51185441) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8218 + ... + 13034.

It is an arithmetic number, because the mean of its divisors is an integer number (2081376).

Almost surely, 2^51185442 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51185442, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (66604032).

51185442 is an abundant number, since it is smaller than the sum of its proper divisors (82022622).

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

51185442 is a wasteful number, since it uses less digits than its factorization.

51185442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4863.

The product of its digits is 6400, while the sum is 30.

The square root of 51185442 is about 7154.4001845018. The cubic root of 51185442 is about 371.2919094725.

The spelling of 51185442 in words is "fifty-one million, one hundred eighty-five thousand, four hundred forty-two".