21020012102087 has 2 divisors, whose sum is σ = 21020012102088. Its totient is φ = 21020012102086.

The previous prime is 21020012102083. The next prime is 21020012102239. The reversal of 21020012102087 is 78020121002012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21020012102087 - 2² = 21020012102083 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21020012102081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510006051043 + 10510006051044.

It is an arithmetic number, because the mean of its divisors is an integer number (10510006051044).

Almost surely, 2^{21020012102087} is an apocalyptic number.

21020012102087 is a deficient number, since it is larger than the sum of its proper divisors (1).

21020012102087 is an equidigital number, since it uses as much as digits as its factorization.

21020012102087 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 896, while the sum is 26.

Adding to 21020012102087 its reverse (78020121002012), we get a palindrome (99040133104099).

The spelling of 21020012102087 in words is "twenty-one trillion, twenty billion, twelve million, one hundred two thousand, eighty-seven".