51172987 has 2 divisors, whose sum is σ = 51172988. Its totient is φ = 51172986.

The previous prime is 51172969. The next prime is 51172997. The reversal of 51172987 is 78927115.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51172987 - 2¹¹ = 51170939 is a prime.

It is not a weakly prime, because it can be changed into another prime (51172997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25586493 + 25586494.

It is an arithmetic number, because the mean of its divisors is an integer number (25586494).

Almost surely, 2^51172987 is an apocalyptic number.

51172987 is a deficient number, since it is larger than the sum of its proper divisors (1).

51172987 is an equidigital number, since it uses as much as digits as its factorization.

51172987 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 35280, while the sum is 40.

The square root of 51172987 is about 7153.5296882029. The cubic root of 51172987 is about 371.2617914306.

The spelling of 51172987 in words is "fifty-one million, one hundred seventy-two thousand, nine hundred eighty-seven".