51540605 has 4 divisors (see below), whose sum is σ = 61848732. Its totient is φ = 41232480.

The previous prime is 51540557. The next prime is 51540607. The reversal of 51540605 is 50604515.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 37687321 + 13853284 = 6139^2 + 3722^2 .

It is not a de Polignac number, because 51540605 - 2¹⁰ = 51539581 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51540607) 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, 5154056 + ... + 5154065.

It is an arithmetic number, because the mean of its divisors is an integer number (15462183).

Almost surely, 2^51540605 is an apocalyptic number.

It is an amenable number.

51540605 is a deficient number, since it is larger than the sum of its proper divisors (10308127).

51540605 is a wasteful number, since it uses less digits than its factorization.

51540605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10308126.

The product of its (nonzero) digits is 3000, while the sum is 26.

The square root of 51540605 is about 7179.1785741824. The cubic root of 51540605 is about 372.1486981171.

The spelling of 51540605 in words is "fifty-one million, five hundred forty thousand, six hundred five".