51260665 has 4 divisors (see below), whose sum is σ = 61512804. Its totient is φ = 41008528.

The previous prime is 51260663. The next prime is 51260681. The reversal of 51260665 is 56606215.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56606215 = 5 ⋅11321243.

It can be written as a sum of positive squares in 2 ways, for example, as 20757136 + 30503529 = 4556^2 + 5523^2 .

It is a cyclic number.

It is not a de Polignac number, because 51260665 - 2¹ = 51260663 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51260663) 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, 5126062 + ... + 5126071.

It is an arithmetic number, because the mean of its divisors is an integer number (15378201).

Almost surely, 2^51260665 is an apocalyptic number.

It is an amenable number.

51260665 is a deficient number, since it is larger than the sum of its proper divisors (10252139).

51260665 is a wasteful number, since it uses less digits than its factorization.

51260665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10252138.

The product of its (nonzero) digits is 10800, while the sum is 31.

The square root of 51260665 is about 7159.6553688009. The cubic root of 51260665 is about 371.4737060889.

The spelling of 51260665 in words is "fifty-one million, two hundred sixty thousand, six hundred sixty-five".