51698221 has 8 divisors (see below), whose sum is σ = 54756320. Its totient is φ = 48673872.

The previous prime is 51698209. The next prime is 51698237. The reversal of 51698221 is 12289615.

51698221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 51698221 - 2¹¹ = 51696173 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 (51698201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5250 + ... + 11443.

It is an arithmetic number, because the mean of its divisors is an integer number (6844540).

Almost surely, 2^51698221 is an apocalyptic number.

It is an amenable number.

51698221 is a deficient number, since it is larger than the sum of its proper divisors (3058099).

51698221 is a wasteful number, since it uses less digits than its factorization.

51698221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16875.

The product of its digits is 8640, while the sum is 34.

The square root of 51698221 is about 7190.1474950101. The cubic root of 51698221 is about 372.5276672692.

The spelling of 51698221 in words is "fifty-one million, six hundred ninety-eight thousand, two hundred twenty-one".