221420434021 has 8 divisors (see below), whose sum is σ = 234457714944. Its totient is φ = 208384547520.

The previous prime is 221420434019. The next prime is 221420434043. The reversal of 221420434021 is 120434024122.

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

It is not a de Polignac number, because 221420434021 - 2¹ = 221420434019 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221420434321) 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, 12405 + ... + 665578.

It is an arithmetic number, because the mean of its divisors is an integer number (29307214368).

Almost surely, 2^221420434021 is an apocalyptic number.

It is an amenable number.

221420434021 is a deficient number, since it is larger than the sum of its proper divisors (13037280923).

221420434021 is a wasteful number, since it uses less digits than its factorization.

221420434021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 697211.

The product of its (nonzero) digits is 3072, while the sum is 25.

Adding to 221420434021 its reverse (120434024122), we get a palindrome (341854458143).

The spelling of 221420434021 in words is "two hundred twenty-one billion, four hundred twenty million, four hundred thirty-four thousand, twenty-one".