216949331791872 has 208 divisors, whose sum is σ = 642854879447680. Its totient is φ = 72302884651008.

The previous prime is 216949331791861. The next prime is 216949331791883. The reversal of 216949331791872 is 278197133949612.

216949331791872 is a `hidden beast` number, since 2 + 1 + 6 + 9 + 49 + 331 + 79 + 187 + 2 = 666.

It is an interprime number because it is at equal distance from previous prime (216949331791861) and next prime (216949331791883).

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a self number, because there is not a number n which added to its sum of digits gives 216949331791872.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 598453293 + ... + 598815699.

Almost surely, 2^{216949331791872} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216949331791872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (321427439723840).

216949331791872 is an abundant number, since it is smaller than the sum of its proper divisors (425905547655808).

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

216949331791872 is an equidigital number, since it uses as much as digits as its factorization.

216949331791872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 367853 (or 367825 counting only the distinct ones).

The product of its digits is 246903552, while the sum is 72.

The spelling of 216949331791872 in words is "two hundred sixteen trillion, nine hundred forty-nine billion, three hundred thirty-one million, seven hundred ninety-one thousand, eight hundred seventy-two".