51251251 has 4 divisors (see below), whose sum is σ = 51267600. Its totient is φ = 51234904.

The previous prime is 51251219. The next prime is 51251269. The reversal of 51251251 is 15215215.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 51251251 - 2⁵ = 51251219 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51251051) 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, 1831 + ... + 10288.

It is an arithmetic number, because the mean of its divisors is an integer number (12816900).

Almost surely, 2^51251251 is an apocalyptic number.

51251251 is a deficient number, since it is larger than the sum of its proper divisors (16349).

51251251 is a wasteful number, since it uses less digits than its factorization.

51251251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16348.

The product of its digits is 500, while the sum is 22.

The square root of 51251251 is about 7158.9979047350. The cubic root of 51251251 is about 371.4509643656.

Adding to 51251251 its reverse (15215215), we get a palindrome (66466466).

The spelling of 51251251 in words is "fifty-one million, two hundred fifty-one thousand, two hundred fifty-one".