21211010099965 has 16 divisors (see below), whose sum is σ = 29094199302528. Its totient is φ = 14542285628736.

The previous prime is 21211010099921. The next prime is 21211010099969. The reversal of 21211010099965 is 56999001011212.

It is a cyclic number.

It is not a de Polignac number, because 21211010099965 - 2³⁵ = 21176650361597 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211010099969) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 49931542 + ... + 50354551.

It is an arithmetic number, because the mean of its divisors is an integer number (1818387456408).

Almost surely, 2^{21211010099965} is an apocalyptic number.

It is an amenable number.

21211010099965 is a deficient number, since it is larger than the sum of its proper divisors (7883189202563).

21211010099965 is a wasteful number, since it uses less digits than its factorization.

21211010099965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100292148.

The product of its (nonzero) digits is 87480, while the sum is 46.

The spelling of 21211010099965 in words is "twenty-one trillion, two hundred eleven billion, ten million, ninety-nine thousand, nine hundred sixty-five".