1211201000001 has 12 divisors (see below), whose sum is σ = 1762098978640. Its totient is φ = 801658215000.

The previous prime is 1211200999993. The next prime is 1211201000057. The reversal of 1211201000001 is 1000001021121.

It is a happy number.

It is not a de Polignac number, because 1211201000001 - 2³ = 1211200999993 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1211201000201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 484091875 + ... + 484094376.

Almost surely, 2^{1211201000001} is an apocalyptic number.

It is an amenable number.

1211201000001 is a deficient number, since it is larger than the sum of its proper divisors (550897978639).

1211201000001 is a wasteful number, since it uses less digits than its factorization.

1211201000001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 968186396 (or 968186393 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 1211201000001 its reverse (1000001021121), we get a palindrome (2211202021122).

The spelling of 1211201000001 in words is "one trillion, two hundred eleven billion, two hundred one million, one", and thus it is an aban number.