221321001021 has 8 divisors (see below), whose sum is σ = 312453177984. Its totient is φ = 138868079040.

The previous prime is 221321001017. The next prime is 221321001059. The reversal of 221321001021 is 120100123122.

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

It is not a de Polignac number, because 221321001021 - 2² = 221321001017 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221321001071) 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, 2169813685 + ... + 2169813786.

It is an arithmetic number, because the mean of its divisors is an integer number (39056647248).

Almost surely, 2^221321001021 is an apocalyptic number.

It is an amenable number.

221321001021 is a deficient number, since it is larger than the sum of its proper divisors (91132176963).

221321001021 is a wasteful number, since it uses less digits than its factorization.

221321001021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4339627491.

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 221321001021 its reverse (120100123122), we get a palindrome (341421124143).

The spelling of 221321001021 in words is "two hundred twenty-one billion, three hundred twenty-one million, one thousand, twenty-one".