51499821 has 8 divisors (see below), whose sum is σ = 69607360. Its totient is φ = 33862752.

The previous prime is 51499801. The next prime is 51499831. The reversal of 51499821 is 12899415.

51499821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 51499821 - 2⁹ = 51499309 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51499821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51499801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 117361 + ... + 117798.

It is an arithmetic number, because the mean of its divisors is an integer number (8700920).

Almost surely, 2^51499821 is an apocalyptic number.

It is an amenable number.

51499821 is a deficient number, since it is larger than the sum of its proper divisors (18107539).

51499821 is a wasteful number, since it uses less digits than its factorization.

51499821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 235235.

The product of its digits is 25920, while the sum is 39.

The square root of 51499821 is about 7176.3375756719. The cubic root of 51499821 is about 372.0505119870.

The spelling of 51499821 in words is "fifty-one million, four hundred ninety-nine thousand, eight hundred twenty-one".