51895809 has 24 divisors (see below), whose sum is σ = 88845120. Its totient is φ = 29653776.

The previous prime is 51895807. The next prime is 51895847. The reversal of 51895809 is 90859815.

51895809 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 51895809 - 2¹ = 51895807 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51895801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13554 + ... + 16955.

It is an arithmetic number, because the mean of its divisors is an integer number (3701880).

Almost surely, 2^51895809 is an apocalyptic number.

It is an amenable number.

51895809 is a deficient number, since it is larger than the sum of its proper divisors (36949311).

51895809 is an equidigital number, since it uses as much as digits as its factorization.

51895809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30531 (or 30519 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 45.

The square root of 51895809 is about 7203.8745824730. The cubic root of 51895809 is about 373.0016579264.

The spelling of 51895809 in words is "fifty-one million, eight hundred ninety-five thousand, eight hundred nine".