21033020087 has 2 divisors, whose sum is σ = 21033020088. Its totient is φ = 21033020086.

The previous prime is 21033020053. The next prime is 21033020179. The reversal of 21033020087 is 78002033012.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21033020087 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21033023087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10516510043 + 10516510044.

It is an arithmetic number, because the mean of its divisors is an integer number (10516510044).

Almost surely, 2^21033020087 is an apocalyptic number.

21033020087 is a deficient number, since it is larger than the sum of its proper divisors (1).

21033020087 is an equidigital number, since it uses as much as digits as its factorization.

21033020087 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2016, while the sum is 26.

Adding to 21033020087 its reverse (78002033012), we get a palindrome (99035053099).

The spelling of 21033020087 in words is "twenty-one billion, thirty-three million, twenty thousand, eighty-seven".