51020681 has 8 divisors (see below), whose sum is σ = 54354720. Its totient is φ = 47751552.

The previous prime is 51020677. The next prime is 51020731. The reversal of 51020681 is 18602015.

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 51020681 - 2² = 51020677 is a prime.

It is a super-2 number, since 2×51020681² = 5206219779407522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51022681) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14600 + ... + 17753.

It is an arithmetic number, because the mean of its divisors is an integer number (6794340).

Almost surely, 2^51020681 is an apocalyptic number.

It is an amenable number.

51020681 is a deficient number, since it is larger than the sum of its proper divisors (3334039).

51020681 is a wasteful number, since it uses less digits than its factorization.

51020681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32455.

The product of its (nonzero) digits is 480, while the sum is 23.

The square root of 51020681 is about 7142.8762414030. The cubic root of 51020681 is about 370.8930969735.

Adding to 51020681 its reverse (18602015), we get a palindrome (69622696).

The spelling of 51020681 in words is "fifty-one million, twenty thousand, six hundred eighty-one".