51979 has 4 divisors (see below), whose sum is σ = 52920. Its totient is φ = 51040.

The previous prime is 51977. The next prime is 51991. The reversal of 51979 is 97915.

51979 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 97915 = 5 ⋅19583.

It is a cyclic number.

It is not a de Polignac number, because 51979 - 2¹ = 51977 is a prime.

It is a Smith number, since the sum of its digits (31) 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.

51979 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 51979.

It is not an unprimeable number, because it can be changed into a prime (51971) 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, 382 + ... + 499.

It is an arithmetic number, because the mean of its divisors is an integer number (13230).

2⁵¹⁹⁷⁹ is an apocalyptic number.

51979 is a gapful number since it is divisible by the number (59) formed by its first and last digit.

51979 is a deficient number, since it is larger than the sum of its proper divisors (941).

51979 is an equidigital number, since it uses as much as digits as its factorization.

51979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 940.

The product of its digits is 2835, while the sum is 31.

The square root of 51979 is about 227.9890348240. The cubic root of 51979 is about 37.3200863574.

The spelling of 51979 in words is "fifty-one thousand, nine hundred seventy-nine".