51665198 has 8 divisors (see below), whose sum is σ = 83459208. Its totient is φ = 23845464.

The previous prime is 51665197. The next prime is 51665203. The reversal of 51665198 is 89156615.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51665191) 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, 993536 + ... + 993587.

It is an arithmetic number, because the mean of its divisors is an integer number (10432401).

Almost surely, 2^51665198 is an apocalyptic number.

51665198 is a deficient number, since it is larger than the sum of its proper divisors (31794010).

51665198 is a wasteful number, since it uses less digits than its factorization.

51665198 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1987138.

The product of its digits is 64800, while the sum is 41.

The square root of 51665198 is about 7187.8507218779. The cubic root of 51665198 is about 372.4483311966.

The spelling of 51665198 in words is "fifty-one million, six hundred sixty-five thousand, one hundred ninety-eight".