21133087 has 2 divisors, whose sum is σ = 21133088. Its totient is φ = 21133086.

The previous prime is 21133027. The next prime is 21133093. The reversal of 21133087 is 78033112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21133087 - 2¹¹ = 21131039 is a prime.

It is a super-2 number, since 2×21133087² = 893214732299138, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21133027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10566543 + 10566544.

It is an arithmetic number, because the mean of its divisors is an integer number (10566544).

Almost surely, 2^21133087 is an apocalyptic number.

21133087 is a deficient number, since it is larger than the sum of its proper divisors (1).

21133087 is an equidigital number, since it uses as much as digits as its factorization.

21133087 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 21133087 is about 4597.0737431544. The cubic root of 21133087 is about 276.4740112936.

Adding to 21133087 its sum of digits (25), we get a palindrome (21133112).

Adding to 21133087 its reverse (78033112), we get a palindrome (99166199).

The spelling of 21133087 in words is "twenty-one million, one hundred thirty-three thousand, eighty-seven".