51786540 has 120 divisors (see below), whose sum is σ = 175024080. Its totient is φ = 12742272.

The previous prime is 51786529. The next prime is 51786557. The reversal of 51786540 is 4568715.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 51786495 and 51786504.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 19831 + ... + 22289.

It is an arithmetic number, because the mean of its divisors is an integer number (1458534).

Almost surely, 2^51786540 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 51786540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (87512040).

51786540 is an abundant number, since it is smaller than the sum of its proper divisors (123237540).

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

51786540 is a wasteful number, since it uses less digits than its factorization.

51786540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2493 (or 2482 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 36.

The square root of 51786540 is about 7196.2865423773. The cubic root of 51786540 is about 372.7396832887.

It can be divided in two parts, 51786 and 540, that added together give a triangular number (52326 = T₃₂₃).

The spelling of 51786540 in words is "fifty-one million, seven hundred eighty-six thousand, five hundred forty".