51405261 has 8 divisors (see below), whose sum is σ = 69181344. Its totient is φ = 33949680.

The previous prime is 51405259. The next prime is 51405269. The reversal of 51405261 is 16250415.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 51405261 - 2¹ = 51405259 is a prime.

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51405269) 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 7 ways as a sum of consecutive naturals, for example, 79750 + ... + 80391.

It is an arithmetic number, because the mean of its divisors is an integer number (8647668).

Almost surely, 2^51405261 is an apocalyptic number.

It is an amenable number.

51405261 is a deficient number, since it is larger than the sum of its proper divisors (17776083).

51405261 is a wasteful number, since it uses less digits than its factorization.

51405261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160251.

The product of its (nonzero) digits is 1200, while the sum is 24.

The square root of 51405261 is about 7169.7462298187. The cubic root of 51405261 is about 371.8226623234.

Adding to 51405261 its reverse (16250415), we get a palindrome (67655676).

It can be divided in two parts, 5140 and 5261, that added together give a palindrome (10401).

The spelling of 51405261 in words is "fifty-one million, four hundred five thousand, two hundred sixty-one".