51531361 has 4 divisors (see below), whose sum is σ = 58892992. Its totient is φ = 44169732.

The previous prime is 51531353. The next prime is 51531377. The reversal of 51531361 is 16313515.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 51531361 - 2³ = 51531353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51531341) 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 3 ways as a sum of consecutive naturals, for example, 3680805 + ... + 3680818.

It is an arithmetic number, because the mean of its divisors is an integer number (14723248).

Almost surely, 2^51531361 is an apocalyptic number.

It is an amenable number.

51531361 is a deficient number, since it is larger than the sum of its proper divisors (7361631).

51531361 is an equidigital number, since it uses as much as digits as its factorization.

51531361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7361630.

The product of its digits is 1350, while the sum is 25.

The square root of 51531361 is about 7178.5347390676. The cubic root of 51531361 is about 372.1264480338.

Adding to 51531361 its reverse (16313515), we get a palindrome (67844876).

The spelling of 51531361 in words is "fifty-one million, five hundred thirty-one thousand, three hundred sixty-one".