53187891 has 8 divisors (see below), whose sum is σ = 74000640. Its totient is φ = 33916872.

The previous prime is 53187887. The next prime is 53187919. The reversal of 53187891 is 19878135.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 53187891 - 2² = 53187887 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (53187391) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 385351 + ... + 385488.

It is an arithmetic number, because the mean of its divisors is an integer number (9250080).

Almost surely, 2^53187891 is an apocalyptic number.

53187891 is the 4613-rd centered pentagonal number.

53187891 is a deficient number, since it is larger than the sum of its proper divisors (20812749).

53187891 is a wasteful number, since it uses less digits than its factorization.

53187891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 770865.

The product of its digits is 60480, while the sum is 42.

The square root of 53187891 is about 7293.0028794729. The cubic root of 53187891 is about 376.0719338568.

Subtracting from 53187891 its sum of digits (42), we obtain a square (53187849 = 7293²).

The spelling of 53187891 in words is "fifty-three million, one hundred eighty-seven thousand, eight hundred ninety-one".