51255515 has 4 divisors (see below), whose sum is σ = 61506624. Its totient is φ = 41004408.

The previous prime is 51255439. The next prime is 51255517. The reversal of 51255515 is 51555215.

51255515 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 51555215 = 5 ⋅10311043.

It is a cyclic number.

It is not a de Polignac number, because 51255515 - 2¹² = 51251419 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51255517) 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 3 ways as a sum of consecutive naturals, for example, 5125547 + ... + 5125556.

It is an arithmetic number, because the mean of its divisors is an integer number (15376656).

Almost surely, 2^51255515 is an apocalyptic number.

51255515 is a deficient number, since it is larger than the sum of its proper divisors (10251109).

51255515 is a wasteful number, since it uses less digits than its factorization.

51255515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10251108.

The product of its digits is 6250, while the sum is 29.

The square root of 51255515 is about 7159.2957055845. The cubic root of 51255515 is about 371.4612654019.

The spelling of 51255515 in words is "fifty-one million, two hundred fifty-five thousand, five hundred fifteen".