221211212012120 has 64 divisors (see below), whose sum is σ = 547778045636640. Its totient is φ = 79728578406400.

The previous prime is 221211212012113. The next prime is 221211212012123. The reversal of 221211212012120 is 21210212112122.

It is a super-2 number, since 2×221211212012120² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 221211212012092 and 221211212012101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221211212012123) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2224519991 + ... + 2224619430.

Almost surely, 2^{221211212012120} is an apocalyptic number.

221211212012120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221211212012120 is an abundant number, since it is smaller than the sum of its proper divisors (326566833624520).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221211212012120 is a wasteful number, since it uses less digits than its factorization.

221211212012120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4449139556 (or 4449139552 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 221211212012120 its reverse (21210212112122), we get a palindrome (242421424124242).

The spelling of 221211212012120 in words is "two hundred twenty-one trillion, two hundred eleven billion, two hundred twelve million, twelve thousand, one hundred twenty".