51287789 has 4 divisors (see below), whose sum is σ = 58614624. Its totient is φ = 43960956.

The previous prime is 51287771. The next prime is 51287801. The reversal of 51287789 is 98778215.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 51287789 - 2¹⁶ = 51222253 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 (51227789) 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, 3663407 + ... + 3663420.

It is an arithmetic number, because the mean of its divisors is an integer number (14653656).

Almost surely, 2^51287789 is an apocalyptic number.

It is an amenable number.

51287789 is a deficient number, since it is larger than the sum of its proper divisors (7326835).

51287789 is an equidigital number, since it uses as much as digits as its factorization.

51287789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7326834.

The product of its digits is 282240, while the sum is 47.

The square root of 51287789 is about 7161.5493435429. The cubic root of 51287789 is about 371.5392149032.

The spelling of 51287789 in words is "fifty-one million, two hundred eighty-seven thousand, seven hundred eighty-nine".