221102780311816 has 96 divisors (see below), whose sum is σ = 471259890523800. Its totient is φ = 96662595456000.

The previous prime is 221102780311811. The next prime is 221102780311867. The reversal of 221102780311816 is 618113087201122.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 62633706909316 + 158469073402500 = 7914146^2 + 12588450^2 .

It is not an unprimeable number, because it can be changed into a prime (221102780311811) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 262424950 + ... + 263266138.

Almost surely, 2^{221102780311816} is an apocalyptic number.

221102780311816 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221102780311816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (235629945261900).

221102780311816 is an abundant number, since it is smaller than the sum of its proper divisors (250157110211984).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221102780311816 is a wasteful number, since it uses less digits than its factorization.

221102780311816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 848247 (or 848224 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 43.

The spelling of 221102780311816 in words is "two hundred twenty-one trillion, one hundred two billion, seven hundred eighty million, three hundred eleven thousand, eight hundred sixteen".