21210200009851 has 2 divisors, whose sum is σ = 21210200009852. Its totient is φ = 21210200009850.

The previous prime is 21210200009849. The next prime is 21210200009959. The reversal of 21210200009851 is 15890000201212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21210200009851 - 2¹ = 21210200009849 is a prime.

Together with 21210200009849, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (21210200009651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605100004925 + 10605100004926.

It is an arithmetic number, because the mean of its divisors is an integer number (10605100004926).

Almost surely, 2^{21210200009851} is an apocalyptic number.

21210200009851 is a deficient number, since it is larger than the sum of its proper divisors (1).

21210200009851 is an equidigital number, since it uses as much as digits as its factorization.

21210200009851 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2880, while the sum is 31.

The spelling of 21210200009851 in words is "twenty-one trillion, two hundred ten billion, two hundred million, nine thousand, eight hundred fifty-one".