51979809 has 8 divisors (see below), whose sum is σ = 79207360. Its totient is φ = 29702736.

The previous prime is 51979789. The next prime is 51979817. The reversal of 51979809 is 90897915.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 51979809 - 2⁹ = 51979297 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (51979849) 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, 1237594 + ... + 1237635.

It is an arithmetic number, because the mean of its divisors is an integer number (9900920).

Almost surely, 2^51979809 is an apocalyptic number.

It is an amenable number.

51979809 is a deficient number, since it is larger than the sum of its proper divisors (27227551).

51979809 is a wasteful number, since it uses less digits than its factorization.

51979809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2475239.

The product of its (nonzero) digits is 204120, while the sum is 48.

The square root of 51979809 is about 7209.7024210435. The cubic root of 51979809 is about 373.2027997272.

The spelling of 51979809 in words is "fifty-one million, nine hundred seventy-nine thousand, eight hundred nine".