51031502251 has 4 divisors (see below), whose sum is σ = 51033222072. Its totient is φ = 51029782432.

The previous prime is 51031502227. The next prime is 51031502293. The reversal of 51031502251 is 15220513015.

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 51031502251 - 2⁹ = 51031501739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51031502201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 814606 + ... + 875011.

It is an arithmetic number, because the mean of its divisors is an integer number (12758305518).

Almost surely, 2^51031502251 is an apocalyptic number.

51031502251 is a deficient number, since it is larger than the sum of its proper divisors (1719821).

51031502251 is a wasteful number, since it uses less digits than its factorization.

51031502251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1719820.

The product of its (nonzero) digits is 1500, while the sum is 25.

The spelling of 51031502251 in words is "fifty-one billion, thirty-one million, five hundred two thousand, two hundred fifty-one".