51325540 has 72 divisors (see below), whose sum is σ = 127092672. Its totient is φ = 17357760.

The previous prime is 51325523. The next prime is 51325559. The reversal of 51325540 is 4552315.

It is a super-2 number, since 2×51325540² = 5268622112583200, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 81025 + ... + 81655.

It is an arithmetic number, because the mean of its divisors is an integer number (1765176).

Almost surely, 2^51325540 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 51325540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (63546336).

51325540 is an abundant number, since it is smaller than the sum of its proper divisors (75767132).

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

51325540 is a wasteful number, since it uses less digits than its factorization.

51325540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 737 (or 728 counting only the distinct ones).

The product of its (nonzero) digits is 3000, while the sum is 25.

The square root of 51325540 is about 7164.1845314034. The cubic root of 51325540 is about 371.6303511967.

Adding to 51325540 its reverse (4552315), we get a palindrome (55877855).

The spelling of 51325540 in words is "fifty-one million, three hundred twenty-five thousand, five hundred forty".