21221010100091 has 8 divisors (see below), whose sum is σ = 21331090080000. Its totient is φ = 21110964537960.

The previous prime is 21221010100067. The next prime is 21221010100139. The reversal of 21221010100091 is 19000101012212.

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 21221010100091 - 2⁴² = 16822963588987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21221010100001) 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, 7367645 + ... + 9834846.

It is an arithmetic number, because the mean of its divisors is an integer number (2666386260000).

Almost surely, 2^{21221010100091} is an apocalyptic number.

21221010100091 is a deficient number, since it is larger than the sum of its proper divisors (110079979909).

21221010100091 is a wasteful number, since it uses less digits than its factorization.

21221010100091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17208889.

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

The spelling of 21221010100091 in words is "twenty-one trillion, two hundred twenty-one billion, ten million, one hundred thousand, ninety-one".