51082640 has 80 divisors (see below), whose sum is σ = 142907520. Its totient is φ = 16588800.

The previous prime is 51082627. The next prime is 51082649. The reversal of 51082640 is 4628015.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×51082640² = 5218872218739200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51082649) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8240 + ... + 13040.

It is an arithmetic number, because the mean of its divisors is an integer number (1786344).

Almost surely, 2^51082640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51082640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (71453760).

51082640 is an abundant number, since it is smaller than the sum of its proper divisors (91824880).

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

51082640 is a wasteful number, since it uses less digits than its factorization.

51082640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4840 (or 4834 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 51082640 is about 7147.2120438672. The cubic root of 51082640 is about 371.0431725175.

The spelling of 51082640 in words is "fifty-one million, eighty-two thousand, six hundred forty".