51375521 has 2 divisors, whose sum is σ = 51375522. Its totient is φ = 51375520.

The previous prime is 51375469. The next prime is 51375523. The reversal of 51375521 is 12557315.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 45711121 + 5664400 = 6761^2 + 2380^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51375521 is a prime.

Together with 51375523, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p_3078614 and since 51375521 and 3078614 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (51375523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25687760 + 25687761.

It is an arithmetic number, because the mean of its divisors is an integer number (25687761).

Almost surely, 2^51375521 is an apocalyptic number.

It is an amenable number.

51375521 is a deficient number, since it is larger than the sum of its proper divisors (1).

51375521 is an equidigital number, since it uses as much as digits as its factorization.

51375521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5250, while the sum is 29.

The square root of 51375521 is about 7167.6719372471. The cubic root of 51375521 is about 371.7509437292.

The spelling of 51375521 in words is "fifty-one million, three hundred seventy-five thousand, five hundred twenty-one".