51189637 has 4 divisors (see below), whose sum is σ = 51207660. Its totient is φ = 51171616.

The previous prime is 51189631. The next prime is 51189647. The reversal of 51189637 is 73698115.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 24295041 + 26894596 = 4929^2 + 5186^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51189637 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51189637.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51189631) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3712 + ... + 10777.

It is an arithmetic number, because the mean of its divisors is an integer number (12801915).

Almost surely, 2^51189637 is an apocalyptic number.

It is an amenable number.

51189637 is a deficient number, since it is larger than the sum of its proper divisors (18023).

51189637 is a wasteful number, since it uses less digits than its factorization.

51189637 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18022.

The product of its digits is 45360, while the sum is 40.

The square root of 51189637 is about 7154.6933547148. The cubic root of 51189637 is about 371.3020525064.

The spelling of 51189637 in words is "fifty-one million, one hundred eighty-nine thousand, six hundred thirty-seven".