11111221012 has 24 divisors (see below), whose sum is σ = 20696256000. Its totient is φ = 5201427840.

The previous prime is 11111221007. The next prime is 11111221013. The reversal of 11111221012 is 21012211111.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 11111220983 and 11111221001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11111221013) 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, 414762 + ... + 440737.

It is an arithmetic number, because the mean of its divisors is an integer number (862344000).

Almost surely, 2^11111221012 is an apocalyptic number.

It is an amenable number.

11111221012 is a deficient number, since it is larger than the sum of its proper divisors (9585034988).

11111221012 is a wasteful number, since it uses less digits than its factorization.

11111221012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 855711 (or 855709 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 11111221012 its reverse (21012211111), we get a palindrome (32123432123).

Subtracting 11111221012 from its reverse (21012211111), we obtain a palindrome (9900990099).

The spelling of 11111221012 in words is "eleven billion, one hundred eleven million, two hundred twenty-one thousand, twelve".