51646140 has 192 divisors, whose sum is σ = 197944320. Its totient is φ = 10886400.

The previous prime is 51646121. The next prime is 51646151. The reversal of 51646140 is 4164615.

51646140 is a `hidden beast` number, since 5 + 1 + 646 + 14 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 48615 + ... + 49665.

It is an arithmetic number, because the mean of its divisors is an integer number (1030960).

Almost surely, 2^51646140 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 51646140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98972160).

51646140 is an abundant number, since it is smaller than the sum of its proper divisors (146298180).

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

51646140 is a wasteful number, since it uses less digits than its factorization.

51646140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1089 (or 1081 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 51646140 is about 7186.5248903764. The cubic root of 51646140 is about 372.4025299382.

It can be divided in two parts, 516 and 46140, that added together give a 6-th power (46656 = 6⁶).

The spelling of 51646140 in words is "fifty-one million, six hundred forty-six thousand, one hundred forty".