216801984400 has 135 divisors (see below), whose sum is σ = 538928539569. Its totient is φ = 83811600000.

The previous prime is 216801984397. The next prime is 216801984403. The reversal of 216801984400 is 4489108612.

The square root of 216801984400 is 465620.

It is a perfect power (a square), and thus also a powerful number.

It is an interprime number because it is at equal distance from previous prime (216801984397) and next prime (216801984403).

It can be written as a sum of positive squares in only one way, i.e., 78048714384 + 138753270016 = 279372^2 + 372496^2 .

It is not an unprimeable number, because it can be changed into a prime (216801984403) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 288684025 + ... + 288684775.

Almost surely, 2^216801984400 is an apocalyptic number.

216801984400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

216801984400 is the 465620-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216801984400

216801984400 is an abundant number, since it is smaller than the sum of its proper divisors (322126555169).

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

216801984400 is an frugal number, since it uses more digits than its factorization.

216801984400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1582 (or 789 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 43.

The spelling of 216801984400 in words is "two hundred sixteen billion, eight hundred one million, nine hundred eighty-four thousand, four hundred".