1211212199999 has 16 divisors (see below), whose sum is σ = 1262997427200. Its totient is φ = 1160097168384.

The previous prime is 1211212199993. The next prime is 1211212200049. The reversal of 1211212199999 is 9999912121121.

It is a cyclic number.

It is not a de Polignac number, because 1211212199999 - 2²⁴ = 1211195422783 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 (1211212199993) 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, 42771257 + ... + 42799565.

It is an arithmetic number, because the mean of its divisors is an integer number (78937339200).

Almost surely, 2^{1211212199999} is an apocalyptic number.

1211212199999 is a deficient number, since it is larger than the sum of its proper divisors (51785227201).

1211212199999 is a wasteful number, since it uses less digits than its factorization.

1211212199999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40082.

The product of its digits is 472392, while the sum is 56.

The spelling of 1211212199999 in words is "one trillion, two hundred eleven billion, two hundred twelve million, one hundred ninety-nine thousand, nine hundred ninety-nine".