1111221312021 has 24 divisors (see below), whose sum is σ = 1649291924280. Its totient is φ = 720436519296.

The previous prime is 1111221312013. The next prime is 1111221312043. The reversal of 1111221312021 is 1202131221111.

It is a happy number.

1111221312021 is a `hidden beast` number, since 1 + 111 + 221 + 312 + 0 + 21 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1013102640900 + 98118671121 = 1006530^2 + 313239^2 .

It is not a de Polignac number, because 1111221312021 - 2³ = 1111221312013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1111221311985 and 1111221312003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1111221312121) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 146670 + ... + 1497983.

It is an arithmetic number, because the mean of its divisors is an integer number (68720496845).

Almost surely, 2^{1111221312021} is an apocalyptic number.

It is an amenable number.

1111221312021 is a deficient number, since it is larger than the sum of its proper divisors (538070612259).

1111221312021 is a wasteful number, since it uses less digits than its factorization.

1111221312021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1646725 (or 1646722 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 18.

Adding to 1111221312021 its reverse (1202131221111), we get a palindrome (2313352533132).

The spelling of 1111221312021 in words is "one trillion, one hundred eleven billion, two hundred twenty-one million, three hundred twelve thousand, twenty-one".