1211200021018 has 16 divisors (see below), whose sum is σ = 1985756179680. Its totient is φ = 550671880176.

The previous prime is 1211200020977. The next prime is 1211200021019. The reversal of 1211200021018 is 8101200021121.

It is a junction number, because it is equal to n+sod(n) for n = 1211200020986 and 1211200021004.

It is not an unprimeable number, because it can be changed into a prime (1211200021019) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 347644648 + ... + 347648131.

It is an arithmetic number, because the mean of its divisors is an integer number (124109761230).

Almost surely, 2^{1211200021018} is an apocalyptic number.

1211200021018 is a deficient number, since it is larger than the sum of its proper divisors (774556158662).

1211200021018 is a wasteful number, since it uses less digits than its factorization.

1211200021018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 695292861.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 1211200021018 its reverse (8101200021121), we get a palindrome (9312400042139).

The spelling of 1211200021018 in words is "one trillion, two hundred eleven billion, two hundred million, twenty-one thousand, eighteen".