51389447 has 4 divisors (see below), whose sum is σ = 51412896. Its totient is φ = 51366000.

The previous prime is 51389431. The next prime is 51389483. The reversal of 51389447 is 74498315.

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

It is a cyclic number.

It is not a de Polignac number, because 51389447 - 2⁴ = 51389431 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 (51389497) 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, 8054 + ... + 12947.

It is an arithmetic number, because the mean of its divisors is an integer number (12853224).

Almost surely, 2^51389447 is an apocalyptic number.

51389447 is a deficient number, since it is larger than the sum of its proper divisors (23449).

51389447 is a wasteful number, since it uses less digits than its factorization.

51389447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23448.

The product of its digits is 120960, while the sum is 41.

The square root of 51389447 is about 7168.6433165558. The cubic root of 51389447 is about 371.7845299965.

The spelling of 51389447 in words is "fifty-one million, three hundred eighty-nine thousand, four hundred forty-seven".