51651515 has 8 divisors (see below), whose sum is σ = 62831328. Its totient is φ = 40754880.

The previous prime is 51651493. The next prime is 51651517. The reversal of 51651515 is 51515615.

It is a happy number.

51651515 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-51651515 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51651517) 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 7 ways as a sum of consecutive naturals, for example, 70391 + ... + 71120.

It is an arithmetic number, because the mean of its divisors is an integer number (7853916).

Almost surely, 2^51651515 is an apocalyptic number.

51651515 is a deficient number, since it is larger than the sum of its proper divisors (11179813).

51651515 is a wasteful number, since it uses less digits than its factorization.

51651515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141589.

The product of its digits is 3750, while the sum is 29.

The square root of 51651515 is about 7186.8988444252. The cubic root of 51651515 is about 372.4154485814.

The spelling of 51651515 in words is "fifty-one million, six hundred fifty-one thousand, five hundred fifteen".