216850435821421 has 4 divisors (see below), whose sum is σ = 216850953377500. Its totient is φ = 216849918265344.

The previous prime is 216850435821391. The next prime is 216850435821427. The reversal of 216850435821421 is 124128534058612.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 33530886223396 + 183319549598025 = 5790586^2 + 13539555^2 .

It is a cyclic number.

It is not a de Polignac number, because 216850435821421 - 2³¹ = 216848288337773 is a prime.

It is a super-2 number, since 2×216850435821421² (a number of 29 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 (216850435821427) 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, 258149046 + ... + 258987703.

It is an arithmetic number, because the mean of its divisors is an integer number (54212738344375).

Almost surely, 2^{216850435821421} is an apocalyptic number.

It is an amenable number.

216850435821421 is a deficient number, since it is larger than the sum of its proper divisors (517556079).

216850435821421 is an equidigital number, since it uses as much as digits as its factorization.

216850435821421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 517556078.

The product of its (nonzero) digits is 3686400, while the sum is 52.

The spelling of 216850435821421 in words is "two hundred sixteen trillion, eight hundred fifty billion, four hundred thirty-five million, eight hundred twenty-one thousand, four hundred twenty-one".