51005251 has 8 divisors (see below), whose sum is σ = 56103408. Its totient is φ = 46367200.

The previous prime is 51005249. The next prime is 51005263. The reversal of 51005251 is 15250015.

It is not a de Polignac number, because 51005251 - 2¹ = 51005249 is a prime.

It is a super-3 number, since 3×51005251³ (a number of 24 digits) contains 333 as substring.

It is a hoax number, since the sum of its digits (19) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51005281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17830 + ... + 20491.

It is an arithmetic number, because the mean of its divisors is an integer number (7012926).

Almost surely, 2^51005251 is an apocalyptic number.

51005251 is a deficient number, since it is larger than the sum of its proper divisors (5098157).

51005251 is an equidigital number, since it uses as much as digits as its factorization.

51005251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38354 (or 38332 counting only the distinct ones).

The product of its (nonzero) digits is 250, while the sum is 19.

The square root of 51005251 is about 7141.7960626162. The cubic root of 51005251 is about 370.8557039178.

Adding to 51005251 its reverse (15250015), we get a palindrome (66255266).

The spelling of 51005251 in words is "fifty-one million, five thousand, two hundred fifty-one".