211220021321 has 8 divisors (see below), whose sum is σ = 213486293664. Its totient is φ = 208955560320.

The previous prime is 211220021297. The next prime is 211220021323. The reversal of 211220021321 is 123120022112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211220021321 is a prime.

It is a super-2 number, since 2×211220021321² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 211220021321.

It is not an unprimeable number, because it can be changed into a prime (211220021323) 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, 217715 + ... + 685448.

It is an arithmetic number, because the mean of its divisors is an integer number (26685786708).

Almost surely, 2^211220021321 is an apocalyptic number.

It is an amenable number.

211220021321 is a deficient number, since it is larger than the sum of its proper divisors (2266272343).

211220021321 is an equidigital number, since it uses as much as digits as its factorization.

211220021321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 905671.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 211220021321 its reverse (123120022112), we get a palindrome (334340043433).

The spelling of 211220021321 in words is "two hundred eleven billion, two hundred twenty million, twenty-one thousand, three hundred twenty-one".