51187551 has 4 divisors (see below), whose sum is σ = 68250072. Its totient is φ = 34125032.

The previous prime is 51187529. The next prime is 51187553. The reversal of 51187551 is 15578115.

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 51187551 - 2⁹ = 51187039 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51187553) 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, 8531256 + ... + 8531261.

It is an arithmetic number, because the mean of its divisors is an integer number (17062518).

Almost surely, 2^51187551 is an apocalyptic number.

51187551 is a deficient number, since it is larger than the sum of its proper divisors (17062521).

51187551 is a wasteful number, since it uses less digits than its factorization.

51187551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17062520.

The product of its digits is 7000, while the sum is 33.

The square root of 51187551 is about 7154.5475747946. The cubic root of 51187551 is about 371.2970088644.

The spelling of 51187551 in words is "fifty-one million, one hundred eighty-seven thousand, five hundred fifty-one".