51972187 has 4 divisors (see below), whose sum is σ = 51990760. Its totient is φ = 51953616.

The previous prime is 51972149. The next prime is 51972191. The reversal of 51972187 is 78127915.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51972187 is a prime.

It is a super-2 number, since 2×51972187² = 5402216443125938, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51972127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4137 + ... + 11002.

It is an arithmetic number, because the mean of its divisors is an integer number (12997690).

Almost surely, 2^51972187 is an apocalyptic number.

51972187 is a deficient number, since it is larger than the sum of its proper divisors (18573).

51972187 is a wasteful number, since it uses less digits than its factorization.

51972187 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18572.

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

The square root of 51972187 is about 7209.1738084194. The cubic root of 51972187 is about 373.1845574466.

The spelling of 51972187 in words is "fifty-one million, nine hundred seventy-two thousand, one hundred eighty-seven".