51340645 has 16 divisors (see below), whose sum is σ = 63948528. Its totient is φ = 39536640.

The previous prime is 51340637. The next prime is 51340649. The reversal of 51340645 is 54604315.

It can be written as a sum of positive squares in 8 ways, for example, as 1313316 + 50027329 = 1146^2 + 7073^2 .

It is not a de Polignac number, because 51340645 - 2³ = 51340637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51340649) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16515 + ... + 19375.

It is an arithmetic number, because the mean of its divisors is an integer number (3996783).

Almost surely, 2^51340645 is an apocalyptic number.

It is an amenable number.

51340645 is a deficient number, since it is larger than the sum of its proper divisors (12607883).

51340645 is a wasteful number, since it uses less digits than its factorization.

51340645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3000.

The product of its (nonzero) digits is 7200, while the sum is 28.

The square root of 51340645 is about 7165.2386561789. The cubic root of 51340645 is about 371.6668043015. Note that the first 3 decimals are identical.

The spelling of 51340645 in words is "fifty-one million, three hundred forty thousand, six hundred forty-five".