51218761 has 8 divisors (see below), whose sum is σ = 56662848. Its totient is φ = 45906000.

The previous prime is 51218743. The next prime is 51218779. The reversal of 51218761 is 16781215.

It is an interprime number because it is at equal distance from previous prime (51218743) and next prime (51218779).

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 51218761 - 2¹¹ = 51216713 is a prime.

It is a super-2 number, since 2×51218761² = 5246722956750242, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (51218261) 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, 32010 + ... + 33571.

It is an arithmetic number, because the mean of its divisors is an integer number (7082856).

Almost surely, 2^51218761 is an apocalyptic number.

It is an amenable number.

51218761 is a deficient number, since it is larger than the sum of its proper divisors (5444087).

51218761 is a wasteful number, since it uses less digits than its factorization.

51218761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65663.

The product of its digits is 3360, while the sum is 31.

The square root of 51218761 is about 7156.7283726574. The cubic root of 51218761 is about 371.3724557588.

Adding to 51218761 its reverse (16781215), we get a palindrome (67999976).

It can be divided in two parts, 51 and 218761, that added together give a palindrome (218812).

The spelling of 51218761 in words is "fifty-one million, two hundred eighteen thousand, seven hundred sixty-one".