51117551 has 4 divisors (see below), whose sum is σ = 51188592. Its totient is φ = 51046512.

The previous prime is 51117533. The next prime is 51117571. The reversal of 51117551 is 15571115.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51117551 is a prime.

It is a super-2 number, since 2×51117551² = 5226008040475202, which contains 22 as substring.

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 51117551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51117511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34430 + ... + 35883.

It is an arithmetic number, because the mean of its divisors is an integer number (12797148).

Almost surely, 2^51117551 is an apocalyptic number.

51117551 is a deficient number, since it is larger than the sum of its proper divisors (71041).

51117551 is an equidigital number, since it uses as much as digits as its factorization.

51117551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71040.

The product of its digits is 875, while the sum is 26.

The square root of 51117551 is about 7149.6539077077. The cubic root of 51117551 is about 371.1276796248.

Adding to 51117551 its reverse (15571115), we get a palindrome (66688666).

The spelling of 51117551 in words is "fifty-one million, one hundred seventeen thousand, five hundred fifty-one".