51681751 has 8 divisors (see below), whose sum is σ = 59696784. Its totient is φ = 44219520.

The previous prime is 51681739. The next prime is 51681779. The reversal of 51681751 is 15718615.

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 51681751 - 2⁵ = 51681719 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51651751) 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, 138000 + ... + 138373.

It is an arithmetic number, because the mean of its divisors is an integer number (7462098).

Almost surely, 2^51681751 is an apocalyptic number.

51681751 is a deficient number, since it is larger than the sum of its proper divisors (8015033).

51681751 is a wasteful number, since it uses less digits than its factorization.

51681751 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 276401.

The product of its digits is 8400, while the sum is 34.

The square root of 51681751 is about 7189.0020865208. The cubic root of 51681751 is about 372.4881031589.

The spelling of 51681751 in words is "fifty-one million, six hundred eighty-one thousand, seven hundred fifty-one".