51286509 has 6 divisors (see below), whose sum is σ = 74080526. Its totient is φ = 34191000.

The previous prime is 51286507. The next prime is 51286511. The reversal of 51286509 is 90568215.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (51286507) and next prime (51286511).

It can be written as a sum of positive squares in only one way, i.e., 35462025 + 15824484 = 5955^2 + 3978^2 .

It is not a de Polignac number, because 51286509 - 2¹ = 51286507 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 (51286507) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2849242 + ... + 2849259.

Almost surely, 2^51286509 is an apocalyptic number.

It is an amenable number.

51286509 is a deficient number, since it is larger than the sum of its proper divisors (22794017).

51286509 is a wasteful number, since it uses less digits than its factorization.

51286509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5698507 (or 5698504 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 36.

The square root of 51286509 is about 7161.4599768483. The cubic root of 51286509 is about 371.5361240170.

The spelling of 51286509 in words is "fifty-one million, two hundred eighty-six thousand, five hundred nine".