221530115021 has 4 divisors (see below), whose sum is σ = 221535130752. Its totient is φ = 221525099292.

The previous prime is 221530114963. The next prime is 221530115039. The reversal of 221530115021 is 120511035122.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 221530115021 - 2²⁶ = 221463006157 is a prime.

It is a super-2 number, since 2×221530115021² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221530175021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2441021 + ... + 2530146.

It is an arithmetic number, because the mean of its divisors is an integer number (55383782688).

Almost surely, 2^221530115021 is an apocalyptic number.

It is an amenable number.

221530115021 is a deficient number, since it is larger than the sum of its proper divisors (5015731).

221530115021 is an equidigital number, since it uses as much as digits as its factorization.

221530115021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5015730.

The product of its (nonzero) digits is 600, while the sum is 23.

It can be divided in two parts, 2215301 and 15021, that added together give a palindrome (2230322).

The spelling of 221530115021 in words is "two hundred twenty-one billion, five hundred thirty million, one hundred fifteen thousand, twenty-one".