51824921 has 4 divisors (see below), whose sum is σ = 51839844. Its totient is φ = 51810000.

The previous prime is 51824917. The next prime is 51824923. The reversal of 51824921 is 12942815.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 37687321 + 14137600 = 6139^2 + 3760^2 .

It is a cyclic number.

It is not a de Polignac number, because 51824921 - 2² = 51824917 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51824923) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 791 + ... + 10211.

It is an arithmetic number, because the mean of its divisors is an integer number (12959961).

Almost surely, 2^51824921 is an apocalyptic number.

It is an amenable number.

51824921 is a deficient number, since it is larger than the sum of its proper divisors (14923).

51824921 is an equidigital number, since it uses as much as digits as its factorization.

51824921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14922.

The product of its digits is 5760, while the sum is 32.

The square root of 51824921 is about 7198.9527710633. The cubic root of 51824921 is about 372.8317444625.

The spelling of 51824921 in words is "fifty-one million, eight hundred twenty-four thousand, nine hundred twenty-one".