51421328 has 80 divisors (see below), whose sum is σ = 122135040. Its totient is φ = 20471808.

The previous prime is 51421319. The next prime is 51421351. The reversal of 51421328 is 82312415.

Its product of digits (1920) is a multiple of the sum of its prime factors (384).

It is a junction number, because it is equal to n+sod(n) for n = 51421297 and 51421306.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 215033 + ... + 215271.

It is an arithmetic number, because the mean of its divisors is an integer number (1526688).

Almost surely, 2^51421328 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 51421328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (61067520).

51421328 is an abundant number, since it is smaller than the sum of its proper divisors (70713712).

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

51421328 is a wasteful number, since it uses less digits than its factorization.

51421328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 384 (or 378 counting only the distinct ones).

The product of its digits is 1920, while the sum is 26.

The square root of 51421328 is about 7170.8666142943. The cubic root of 51421328 is about 371.8613967013.

The spelling of 51421328 in words is "fifty-one million, four hundred twenty-one thousand, three hundred twenty-eight".