21090199901121 has 96 divisors (see below), whose sum is σ = 33825130440192. Its totient is φ = 12578629916160.

The previous prime is 21090199901119. The next prime is 21090199901131. The reversal of 21090199901121 is 12110999109012.

It is not a de Polignac number, because 21090199901121 - 2¹ = 21090199901119 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21090199901131) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1244765176 + ... + 1244782118.

It is an arithmetic number, because the mean of its divisors is an integer number (352345108752).

Almost surely, 2^{21090199901121} is an apocalyptic number.

It is an amenable number.

21090199901121 is a deficient number, since it is larger than the sum of its proper divisors (12734930539071).

21090199901121 is a wasteful number, since it uses less digits than its factorization.

21090199901121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18103 (or 18100 counting only the distinct ones).

The product of its (nonzero) digits is 26244, while the sum is 45.

The spelling of 21090199901121 in words is "twenty-one trillion, ninety billion, one hundred ninety-nine million, nine hundred one thousand, one hundred twenty-one".