51331261 has 8 divisors (see below), whose sum is σ = 51962240. Its totient is φ = 50703408.

The previous prime is 51331253. The next prime is 51331327. The reversal of 51331261 is 16213315.

It is a happy number.

51331261 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 51331261 - 2³ = 51331253 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 (51331361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 52600 + ... + 53566.

It is an arithmetic number, because the mean of its divisors is an integer number (6495280).

Almost surely, 2^51331261 is an apocalyptic number.

It is an amenable number.

51331261 is a deficient number, since it is larger than the sum of its proper divisors (630979).

51331261 is a wasteful number, since it uses less digits than its factorization.

51331261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1563.

The product of its digits is 540, while the sum is 22.

The square root of 51331261 is about 7164.5837981002. The cubic root of 51331261 is about 371.6441586062.

Adding to 51331261 its reverse (16213315), we get a palindrome (67544576).

The spelling of 51331261 in words is "fifty-one million, three hundred thirty-one thousand, two hundred sixty-one".