51261643 has 2 divisors, whose sum is σ = 51261644. Its totient is φ = 51261642.

The previous prime is 51261629. The next prime is 51261649. The reversal of 51261643 is 34616215.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51261643 - 2⁵ = 51261611 is a prime.

It is not a weakly prime, because it can be changed into another prime (51261649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25630821 + 25630822.

It is an arithmetic number, because the mean of its divisors is an integer number (25630822).

Almost surely, 2^51261643 is an apocalyptic number.

51261643 is a deficient number, since it is larger than the sum of its proper divisors (1).

51261643 is an equidigital number, since it uses as much as digits as its factorization.

51261643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4320, while the sum is 28.

The square root of 51261643 is about 7159.7236678520. The cubic root of 51261643 is about 371.4760685174.

Adding to 51261643 its reverse (34616215), we get a palindrome (85877858).

The spelling of 51261643 in words is "fifty-one million, two hundred sixty-one thousand, six hundred forty-three".