51653440 has 112 divisors (see below), whose sum is σ = 131088384. Its totient is φ = 19353600.

The previous prime is 51653417. The next prime is 51653447. The reversal of 51653440 is 4435615.

51653440 is nontrivially palindromic in base 3.

It is a junction number, because it is equal to n+sod(n) for n = 51653399 and 51653408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51653447) 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, 406657 + ... + 406783.

It is an arithmetic number, because the mean of its divisors is an integer number (1170432).

Almost surely, 2^51653440 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 51653440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (65544192).

51653440 is an abundant number, since it is smaller than the sum of its proper divisors (79434944).

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

51653440 is a wasteful number, since it uses less digits than its factorization.

51653440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 216 (or 206 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 28.

The square root of 51653440 is about 7187.0327674222. The cubic root of 51653440 is about 372.4200750403.

It can be divided in two parts, 516 and 53440, that added together give a triangular number (53956 = T₃₂₈).

The spelling of 51653440 in words is "fifty-one million, six hundred fifty-three thousand, four hundred forty".