221451545154121 has 16 divisors (see below), whose sum is σ = 227362671986688. Its totient is φ = 215564779584000.

The previous prime is 221451545154061. The next prime is 221451545154127. The reversal of 221451545154121 is 121451545154122.

It is a cyclic number.

It is not a de Polignac number, because 221451545154121 - 2¹¹ = 221451545152073 is a prime.

It is a super-2 number, since 2×221451545154121² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221451545154127) 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, 218767665 + ... + 219777601.

It is an arithmetic number, because the mean of its divisors is an integer number (14210166999168).

Almost surely, 2^{221451545154121} is an apocalyptic number.

It is an amenable number.

221451545154121 is a deficient number, since it is larger than the sum of its proper divisors (5911126832567).

221451545154121 is a wasteful number, since it uses less digits than its factorization.

221451545154121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1021992.

The product of its digits is 320000, while the sum is 43.

Subtracting from 221451545154121 its reverse (121451545154122), we obtain a palindrome (99999999999999).

The spelling of 221451545154121 in words is "two hundred twenty-one trillion, four hundred fifty-one billion, five hundred forty-five million, one hundred fifty-four thousand, one hundred twenty-one".