51500040 has 64 divisors (see below), whose sum is σ = 156643200. Its totient is φ = 13542912.

The previous prime is 51500023. The next prime is 51500069. The reversal of 51500040 is 4000515.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a junction number, because it is equal to n+sod(n) for n = 51499992 and 51500019.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5821 + ... + 11699.

It is an arithmetic number, because the mean of its divisors is an integer number (2447550).

Almost surely, 2^51500040 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 51500040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (78321600).

51500040 is an abundant number, since it is smaller than the sum of its proper divisors (105143160).

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

51500040 is a wasteful number, since it uses less digits than its factorization.

51500040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5966 (or 5962 counting only the distinct ones).

The product of its (nonzero) digits is 100, while the sum is 15.

The square root of 51500040 is about 7176.3528341352. The cubic root of 51500040 is about 372.0510393607.

Adding to 51500040 its reverse (4000515), we get a palindrome (55500555).

The spelling of 51500040 in words is "fifty-one million, five hundred thousand, forty".