51564643 has 32 divisors (see below), whose sum is σ = 61286400. Its totient is φ = 42996096.

The previous prime is 51564631. The next prime is 51564647. The reversal of 51564643 is 34646515.

It is not a de Polignac number, because 51564643 - 2⁹ = 51564131 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 51564599 and 51564608.

It is not an unprimeable number, because it can be changed into a prime (51564647) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 652678 + ... + 652756.

It is an arithmetic number, because the mean of its divisors is an integer number (1915200).

Almost surely, 2^51564643 is an apocalyptic number.

51564643 is a deficient number, since it is larger than the sum of its proper divisors (9721757).

51564643 is a wasteful number, since it uses less digits than its factorization.

51564643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 211.

The product of its digits is 43200, while the sum is 34.

The square root of 51564643 is about 7180.8525259888. The cubic root of 51564643 is about 372.2065445473.

The spelling of 51564643 in words is "fifty-one million, five hundred sixty-four thousand, six hundred forty-three".