1211111201001 has 32 divisors (see below), whose sum is σ = 1841441817600. Its totient is φ = 701414498304.

The previous prime is 1211111200979. The next prime is 1211111201009. The reversal of 1211111201001 is 1001021111121.

It is not a de Polignac number, because 1211111201001 - 2¹⁴ = 1211111184617 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1211111201009) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12830425 + ... + 12924473.

It is an arithmetic number, because the mean of its divisors is an integer number (57545056800).

Almost surely, 2^{1211111201001} is an apocalyptic number.

It is an amenable number.

1211111201001 is a deficient number, since it is larger than the sum of its proper divisors (630330616599).

1211111201001 is a wasteful number, since it uses less digits than its factorization.

1211111201001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113505.

The product of its (nonzero) digits is 4, while the sum is 12.

Adding to 1211111201001 its reverse (1001021111121), we get a palindrome (2212132312122).

The spelling of 1211111201001 in words is "one trillion, two hundred eleven billion, one hundred eleven million, two hundred one thousand, one".