51251605 has 8 divisors (see below), whose sum is σ = 61566264. Its totient is φ = 40958400.

The previous prime is 51251597. The next prime is 51251611. The reversal of 51251605 is 50615215.

It can be written as a sum of positive squares in 4 ways, for example, as 14641 + 51236964 = 121^2 + 7158^2 .

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

It is not a de Polignac number, because 51251605 - 2³ = 51251597 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51251605.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 475 + ... + 10135.

It is an arithmetic number, because the mean of its divisors is an integer number (7695783).

Almost surely, 2^51251605 is an apocalyptic number.

It is an amenable number.

51251605 is a deficient number, since it is larger than the sum of its proper divisors (10314659).

51251605 is a wasteful number, since it uses less digits than its factorization.

51251605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10727.

The product of its (nonzero) digits is 1500, while the sum is 25.

The square root of 51251605 is about 7159.0226288230. The cubic root of 51251605 is about 371.4518195860.

The spelling of 51251605 in words is "fifty-one million, two hundred fifty-one thousand, six hundred five".