1211011001000 has 64 divisors (see below), whose sum is σ = 2925177615360. Its totient is φ = 468778440000.

The previous prime is 1211011000993. The next prime is 1211011001009. The reversal of 1211011001000 is 1001101121.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (8).

It is not an unprimeable number, because it can be changed into a prime (1211011001009) 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, 19501436 + ... + 19563435.

It is an arithmetic number, because the mean of its divisors is an integer number (45705900240).

Almost surely, 2^{1211011001000} is an apocalyptic number.

1211011001000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1211011001000 is an abundant number, since it is smaller than the sum of its proper divisors (1714166614360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1211011001000 is a wasteful number, since it uses less digits than its factorization.

1211011001000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39064923 (or 39064909 counting only the distinct ones).

The product of its (nonzero) digits is 2, while the sum is 8.

Adding to 1211011001000 its reverse (1001101121), we get a palindrome (1212012102121).

The spelling of 1211011001000 in words is "one trillion, two hundred eleven billion, eleven million, one thousand".