51684420 has 48 divisors (see below), whose sum is σ = 153232128. Its totient is φ = 12971520.

The previous prime is 51684401. The next prime is 51684433. The reversal of 51684420 is 2448615.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24316 + ... + 26355.

It is an arithmetic number, because the mean of its divisors is an integer number (3192336).

Almost surely, 2^51684420 is an apocalyptic number.

It is an amenable number.

51684420 is an abundant number, since it is smaller than the sum of its proper divisors (101547708).

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

51684420 is a wasteful number, since it uses less digits than its factorization.

51684420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50700 (or 50698 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 30.

The square root of 51684420 is about 7189.1877148952. The cubic root of 51684420 is about 372.4945151813.

The spelling of 51684420 in words is "fifty-one million, six hundred eighty-four thousand, four hundred twenty".