51287169 has 4 divisors (see below), whose sum is σ = 68382896. Its totient is φ = 34191444.

The previous prime is 51287161. The next prime is 51287179. The reversal of 51287169 is 96178215.

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 not a de Polignac number, because 51287169 - 2³ = 51287161 is a prime.

It is a super-2 number, since 2×51287169² = 5260747408069122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51287161) 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, 8547859 + ... + 8547864.

It is an arithmetic number, because the mean of its divisors is an integer number (17095724).

Almost surely, 2^51287169 is an apocalyptic number.

It is an amenable number.

51287169 is a deficient number, since it is larger than the sum of its proper divisors (17095727).

51287169 is a wasteful number, since it uses less digits than its factorization.

51287169 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17095726.

The product of its digits is 30240, while the sum is 39.

The square root of 51287169 is about 7161.5060566895. The cubic root of 51287169 is about 371.5377177616.

The spelling of 51287169 in words is "fifty-one million, two hundred eighty-seven thousand, one hundred sixty-nine".