21187192 has 24 divisors (see below), whose sum is σ = 43019640. Its totient is φ = 9778080.

The previous prime is 21187189. The next prime is 21187193. The reversal of 21187192 is 29178112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21187193) 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 5 ways as a sum of consecutive naturals, for example, 6484 + ... + 9187.

It is an arithmetic number, because the mean of its divisors is an integer number (1792485).

Almost surely, 2^21187192 is an apocalyptic number.

It is an amenable number.

21187192 is an abundant number, since it is smaller than the sum of its proper divisors (21832448).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21187192 is a wasteful number, since it uses less digits than its factorization.

21187192 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15703 (or 15686 counting only the distinct ones).

The product of its digits is 2016, while the sum is 31.

The square root of 21187192 is about 4602.9547032314. The cubic root of 21187192 is about 276.7097534547.

The spelling of 21187192 in words is "twenty-one million, one hundred eighty-seven thousand, one hundred ninety-two".