51303991 has 8 divisors (see below), whose sum is σ = 52083200. Its totient is φ = 50530392.

The previous prime is 51303983. The next prime is 51304003. The reversal of 51303991 is 19930315.

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 51303991 - 2³ = 51303983 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 (51303191) 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, 19246 + ... + 21748.

It is an arithmetic number, because the mean of its divisors is an integer number (6510400).

Almost surely, 2^51303991 is an apocalyptic number.

51303991 is a deficient number, since it is larger than the sum of its proper divisors (779209).

51303991 is a wasteful number, since it uses less digits than its factorization.

51303991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2805.

The product of its (nonzero) digits is 3645, while the sum is 31.

The square root of 51303991 is about 7162.6804340275. The cubic root of 51303991 is about 371.5783343161.

The spelling of 51303991 in words is "fifty-one million, three hundred three thousand, nine hundred ninety-one".