221213132120421 has 16 divisors (see below), whose sum is σ = 374540752796800. Its totient is φ = 126407504068704.

The previous prime is 221213132120411. The next prime is 221213132120441. The reversal of 221213132120421 is 124021231312122.

221213132120421 is a `hidden beast` number, since 2 + 2 + 1 + 2 + 13 + 13 + 212 + 0 + 421 = 666.

It is not a de Polignac number, because 221213132120421 - 2²⁵ = 221213098565989 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221213132120411) 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, 585219926056 + ... + 585219926433.

It is an arithmetic number, because the mean of its divisors is an integer number (23408797049800).

Almost surely, 2^{221213132120421} is an apocalyptic number.

221213132120421 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

221213132120421 is a deficient number, since it is larger than the sum of its proper divisors (153327620676379).

221213132120421 is a wasteful number, since it uses less digits than its factorization.

221213132120421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1170439852505 (or 1170439852499 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

Adding to 221213132120421 its reverse (124021231312122), we get a palindrome (345234363432543).

The spelling of 221213132120421 in words is "two hundred twenty-one trillion, two hundred thirteen billion, one hundred thirty-two million, one hundred twenty thousand, four hundred twenty-one".