21032887 has 4 divisors (see below), whose sum is σ = 21109096. Its totient is φ = 20956680.

The previous prime is 21032873. The next prime is 21032897. The reversal of 21032887 is 78823012.

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 21032887 - 2¹⁹ = 20508599 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21032807) 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, 37689 + ... + 38242.

It is an arithmetic number, because the mean of its divisors is an integer number (5277274).

Almost surely, 2^21032887 is an apocalyptic number.

21032887 is a deficient number, since it is larger than the sum of its proper divisors (76209).

21032887 is an equidigital number, since it uses as much as digits as its factorization.

21032887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76208.

The product of its (nonzero) digits is 5376, while the sum is 31.

The square root of 21032887 is about 4586.1625570841. The cubic root of 21032887 is about 276.0363627439.

Adding to 21032887 its reverse (78823012), we get a palindrome (99855899).

The spelling of 21032887 in words is "twenty-one million, thirty-two thousand, eight hundred eighty-seven".