51319421 has 2 divisors, whose sum is σ = 51319422. Its totient is φ = 51319420.

The previous prime is 51319397. The next prime is 51319451. The reversal of 51319421 is 12491315.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25867396 + 25452025 = 5086^2 + 5045^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51319421 is a prime.

It is a Chen prime.

It is equal to p_3075425 and since 51319421 and 3075425 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51319451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25659710 + 25659711.

It is an arithmetic number, because the mean of its divisors is an integer number (25659711).

Almost surely, 2^51319421 is an apocalyptic number.

It is an amenable number.

51319421 is a deficient number, since it is larger than the sum of its proper divisors (1).

51319421 is an equidigital number, since it uses as much as digits as its factorization.

51319421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1080, while the sum is 26.

The square root of 51319421 is about 7163.7574637895. The cubic root of 51319421 is about 371.6155820941.

The spelling of 51319421 in words is "fifty-one million, three hundred nineteen thousand, four hundred twenty-one".