1211021212099 has 4 divisors (see below), whose sum is σ = 1211702711464. Its totient is φ = 1210339712736.

The previous prime is 1211021212091. The next prime is 1211021212103. The reversal of 1211021212099 is 9902121201121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1211021212099 - 2³ = 1211021212091 is a prime.

It is a super-2 number, since 2×1211021212099² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1211021212099.

It is not an unprimeable number, because it can be changed into a prime (1211021212091) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 340747017 + ... + 340750570.

It is an arithmetic number, because the mean of its divisors is an integer number (302925677866).

Almost surely, 2^{1211021212099} is an apocalyptic number.

1211021212099 is a deficient number, since it is larger than the sum of its proper divisors (681499365).

1211021212099 is an equidigital number, since it uses as much as digits as its factorization.

1211021212099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 681499364.

The product of its (nonzero) digits is 1296, while the sum is 31.

The spelling of 1211021212099 in words is "one trillion, two hundred eleven billion, twenty-one million, two hundred twelve thousand, ninety-nine".