51336421 has 4 divisors (see below), whose sum is σ = 51464844. Its totient is φ = 51208000.

The previous prime is 51336419. The next prime is 51336433. The reversal of 51336421 is 12463315.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 30305025 + 21031396 = 5505^2 + 4586^2 .

It is a cyclic number.

It is not a de Polignac number, because 51336421 - 2¹ = 51336419 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51336401) 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, 63610 + ... + 64411.

It is an arithmetic number, because the mean of its divisors is an integer number (12866211).

Almost surely, 2^51336421 is an apocalyptic number.

It is an amenable number.

51336421 is a deficient number, since it is larger than the sum of its proper divisors (128423).

51336421 is a wasteful number, since it uses less digits than its factorization.

51336421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128422.

The product of its digits is 2160, while the sum is 25.

The square root of 51336421 is about 7164.9438937091. The cubic root of 51336421 is about 371.6566111843.

Adding to 51336421 its reverse (12463315), we get a palindrome (63799736).

The spelling of 51336421 in words is "fifty-one million, three hundred thirty-six thousand, four hundred twenty-one".