21212001010091 has 8 divisors (see below), whose sum is σ = 21581109672000. Its totient is φ = 20843211789000.

The previous prime is 21212001010073. The next prime is 21212001010103. The reversal of 21212001010091 is 19001010021212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21212001010091 - 2¹⁸ = 21212000747947 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21212001010051) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 79726241 + ... + 79991858.

It is an arithmetic number, because the mean of its divisors is an integer number (2697638709000).

Almost surely, 2^{21212001010091} is an apocalyptic number.

21212001010091 is a deficient number, since it is larger than the sum of its proper divisors (369108661909).

21212001010091 is a wasteful number, since it uses less digits than its factorization.

21212001010091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159720409.

The product of its (nonzero) digits is 72, while the sum is 20.

The spelling of 21212001010091 in words is "twenty-one trillion, two hundred twelve billion, one million, ten thousand, ninety-one".