51493728 has 192 divisors, whose sum is σ = 165279744. Its totient is φ = 13939200.

The previous prime is 51493723. The next prime is 51493733. The reversal of 51493728 is 82739415.

It is an interprime number because it is at equal distance from previous prime (51493723) and next prime (51493733).

It is a Harshad number since it is a multiple of its sum of digits (39).

Its product of digits (60480) is a multiple of the sum of its prime divisors (60).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51493723) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1661073 + ... + 1661103.

It is an arithmetic number, because the mean of its divisors is an integer number (860832).

Almost surely, 2^51493728 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 51493728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82639872).

51493728 is an abundant number, since it is smaller than the sum of its proper divisors (113786016).

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

51493728 is a wasteful number, since it uses less digits than its factorization.

51493728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90 (or 60 counting only the distinct ones).

The product of its digits is 60480, while the sum is 39.

The square root of 51493728 is about 7175.9130429514. The cubic root of 51493728 is about 372.0358388410.

The spelling of 51493728 in words is "fifty-one million, four hundred ninety-three thousand, seven hundred twenty-eight".