11221212321 has 48 divisors (see below), whose sum is σ = 19326048768. Its totient is φ = 6194188800.

The previous prime is 11221212319. The next prime is 11221212347. The reversal of 11221212321 is 12321212211.

11221212321 is a `hidden beast` number, since 112 + 21 + 212 + 321 = 666.

It is not a de Polignac number, because 11221212321 - 2¹ = 11221212319 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 11221212294 and 11221212303.

It is not an unprimeable number, because it can be changed into a prime (11221212521) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 55366 + ... + 159711.

It is an arithmetic number, because the mean of its divisors is an integer number (402626016).

Almost surely, 2^11221212321 is an apocalyptic number.

11221212321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

11221212321 is a deficient number, since it is larger than the sum of its proper divisors (8104836447).

11221212321 is a wasteful number, since it uses less digits than its factorization.

11221212321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215142 (or 215139 counting only the distinct ones).

The product of its digits is 96, while the sum is 18.

Adding to 11221212321 its reverse (12321212211), we get a palindrome (23542424532).

The spelling of 11221212321 in words is "eleven billion, two hundred twenty-one million, two hundred twelve thousand, three hundred twenty-one".