21210012010987 has 4 divisors (see below), whose sum is σ = 21210091232040. Its totient is φ = 21209932789936.

The previous prime is 21210012010939. The next prime is 21210012011047. The reversal of 21210012010987 is 78901021001212.

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 21210012010987 - 2¹⁵ = 21210011978219 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21210012010907) 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, 39207562 + ... + 39744847.

It is an arithmetic number, because the mean of its divisors is an integer number (5302522808010).

Almost surely, 2^{21210012010987} is an apocalyptic number.

21210012010987 is a deficient number, since it is larger than the sum of its proper divisors (79221053).

21210012010987 is an equidigital number, since it uses as much as digits as its factorization.

21210012010987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79221052.

The product of its (nonzero) digits is 4032, while the sum is 34.

The spelling of 21210012010987 in words is "twenty-one trillion, two hundred ten billion, twelve million, ten thousand, nine hundred eighty-seven".