1021201209999 has 8 divisors (see below), whose sum is σ = 1512890681520. Its totient is φ = 680800806648.

The previous prime is 1021201209989. The next prime is 1021201210019. The reversal of 1021201209999 is 9999021021201.

It is not a de Polignac number, because 1021201209999 - 2¹² = 1021201205903 is a prime.

It is a super-2 number, since 2×1021201209999² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021201209949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18911133492 + ... + 18911133545.

It is an arithmetic number, because the mean of its divisors is an integer number (189111335190).

Almost surely, 2^{1021201209999} is an apocalyptic number.

1021201209999 is a deficient number, since it is larger than the sum of its proper divisors (491689471521).

1021201209999 is an equidigital number, since it uses as much as digits as its factorization.

1021201209999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37822267046 (or 37822267040 counting only the distinct ones).

The product of its (nonzero) digits is 52488, while the sum is 45.

The spelling of 1021201209999 in words is "one trillion, twenty-one billion, two hundred one million, two hundred nine thousand, nine hundred ninety-nine".