51100221 has 8 divisors (see below), whose sum is σ = 68528160. Its totient is φ = 33869552.

The previous prime is 51100213. The next prime is 51100229. The reversal of 51100221 is 12200115.

It is an interprime number because it is at equal distance from previous prime (51100213) and next prime (51100229).

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 51100221 - 2³ = 51100213 is a prime.

It is a super-2 number, since 2×51100221² = 5222465172497682, which contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 51100197 and 51100206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51100229) 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, 48711 + ... + 49748.

It is an arithmetic number, because the mean of its divisors is an integer number (8566020).

Almost surely, 2^51100221 is an apocalyptic number.

It is an amenable number.

51100221 is a deficient number, since it is larger than the sum of its proper divisors (17427939).

51100221 is a wasteful number, since it uses less digits than its factorization.

51100221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98635.

The product of its (nonzero) digits is 20, while the sum is 12.

The square root of 51100221 is about 7148.4418581954. The cubic root of 51100221 is about 371.0857346729.

Adding to 51100221 its reverse (12200115), we get a palindrome (63300336).

The spelling of 51100221 in words is "fifty-one million, one hundred thousand, two hundred twenty-one".