216781031376 has 320 divisors, whose sum is σ = 790544957440. Its totient is φ = 55328417280.

The previous prime is 216781031353. The next prime is 216781031413. The reversal of 216781031376 is 673130187612.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1129731 + ... + 1307613.

It is an arithmetic number, because the mean of its divisors is an integer number (2470452992).

Almost surely, 2^216781031376 is an apocalyptic number.

216781031376 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 216781031376, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (395272478720).

216781031376 is an abundant number, since it is smaller than the sum of its proper divisors (573763926064).

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

216781031376 is a wasteful number, since it uses less digits than its factorization.

216781031376 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177951 (or 177939 counting only the distinct ones).

The product of its (nonzero) digits is 254016, while the sum is 45.

The spelling of 216781031376 in words is "two hundred sixteen billion, seven hundred eighty-one million, thirty-one thousand, three hundred seventy-six".