51534540 has 72 divisors (see below), whose sum is σ = 160157088. Its totient is φ = 13405440.

The previous prime is 51534523. The next prime is 51534541. The reversal of 51534540 is 4543515.

It is not an unprimeable number, because it can be changed into a prime (51534541) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3889 + ... + 10871.

It is an arithmetic number, because the mean of its divisors is an integer number (2224404).

Almost surely, 2^51534540 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 51534540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80078544).

51534540 is an abundant number, since it is smaller than the sum of its proper divisors (108622548).

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

51534540 is a wasteful number, since it uses less digits than its factorization.

51534540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7039 (or 7034 counting only the distinct ones).

The product of its (nonzero) digits is 6000, while the sum is 27.

The square root of 51534540 is about 7178.7561596700. The cubic root of 51534540 is about 372.1341001097.

Subtracting from 51534540 its reverse (4543515), we obtain a square (46991025 = 6855²).

The spelling of 51534540 in words is "fifty-one million, five hundred thirty-four thousand, five hundred forty".