51809328 has 40 divisors (see below), whose sum is σ = 148713200. Its totient is φ = 17269632.

The previous prime is 51809299. The next prime is 51809357. The reversal of 51809328 is 82390815.

It is an interprime number because it is at equal distance from previous prime (51809299) and next prime (51809357).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 51809292 and 51809301.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 59533 + ... + 60396.

It is an arithmetic number, because the mean of its divisors is an integer number (3717830).

Almost surely, 2^51809328 is an apocalyptic number.

It is an amenable number.

51809328 is an abundant number, since it is smaller than the sum of its proper divisors (96903872).

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

51809328 is a wasteful number, since it uses less digits than its factorization.

51809328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 119946 (or 119934 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

The square root of 51809328 is about 7197.8696848443. The cubic root of 51809328 is about 372.7943483704.

The spelling of 51809328 in words is "fifty-one million, eight hundred nine thousand, three hundred twenty-eight".