21221111099 has 2 divisors, whose sum is σ = 21221111100. Its totient is φ = 21221111098.

The previous prime is 21221111089. The next prime is 21221111113. The reversal of 21221111099 is 99011112212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21221111099 - 2¹⁶ = 21221045563 is a prime.

It is a super-2 number, since 2×21221111099² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21221111029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610555549 + 10610555550.

It is an arithmetic number, because the mean of its divisors is an integer number (10610555550).

Almost surely, 2^21221111099 is an apocalyptic number.

21221111099 is a deficient number, since it is larger than the sum of its proper divisors (1).

21221111099 is an equidigital number, since it uses as much as digits as its factorization.

21221111099 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 29.

The spelling of 21221111099 in words is "twenty-one billion, two hundred twenty-one million, one hundred eleven thousand, ninety-nine".