51447391 has 2 divisors, whose sum is σ = 51447392. Its totient is φ = 51447390.

The previous prime is 51447373. The next prime is 51447437. The reversal of 51447391 is 19374415.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 51447391 - 2⁵ = 51447359 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51447371) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25723695 + 25723696.

It is an arithmetic number, because the mean of its divisors is an integer number (25723696).

Almost surely, 2^51447391 is an apocalyptic number.

51447391 is a deficient number, since it is larger than the sum of its proper divisors (1).

51447391 is an equidigital number, since it uses as much as digits as its factorization.

51447391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15120, while the sum is 34.

The square root of 51447391 is about 7172.6836679168. The cubic root of 51447391 is about 371.9242123135.

The spelling of 51447391 in words is "fifty-one million, four hundred forty-seven thousand, three hundred ninety-one".