51998218 has 8 divisors (see below), whose sum is σ = 80686980. Its totient is φ = 25102560.

The previous prime is 51998203. The next prime is 51998227. The reversal of 51998218 is 81289915.

It can be written as a sum of positive squares in 2 ways, for example, as 45118089 + 6880129 = 6717^2 + 2623^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 448203 + ... + 448318.

Almost surely, 2^51998218 is an apocalyptic number.

51998218 is a gapful number since it is divisible by the number (58) formed by its first and last digit.

51998218 is a deficient number, since it is larger than the sum of its proper divisors (28688762).

51998218 is a wasteful number, since it uses less digits than its factorization.

51998218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 896552.

The product of its digits is 51840, while the sum is 43.

The square root of 51998218 is about 7210.9789904007. The cubic root of 51998218 is about 373.2468519568.

The spelling of 51998218 in words is "fifty-one million, nine hundred ninety-eight thousand, two hundred eighteen".