51887491 has 4 divisors (see below), whose sum is σ = 52767000. Its totient is φ = 51007984.

The previous prime is 51887447. The next prime is 51887527. The reversal of 51887491 is 19478815.

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 51887491 - 2¹³ = 51879299 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51887411) 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, 439666 + ... + 439783.

It is an arithmetic number, because the mean of its divisors is an integer number (13191750).

Almost surely, 2^51887491 is an apocalyptic number.

51887491 is a deficient number, since it is larger than the sum of its proper divisors (879509).

51887491 is an equidigital number, since it uses as much as digits as its factorization.

51887491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 879508.

The product of its digits is 80640, while the sum is 43.

The square root of 51887491 is about 7203.2972311296. The cubic root of 51887491 is about 372.9817282915.

The spelling of 51887491 in words is "fifty-one million, eight hundred eighty-seven thousand, four hundred ninety-one".