216247655238520 has 128 divisors (see below), whose sum is σ = 504378653760000. Its totient is φ = 83343289469440.

The previous prime is 216247655238497. The next prime is 216247655238529. The reversal of 216247655238520 is 25832556742612.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (58).

It is a Sastry number since concatenated with its successor gives a square.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216247655238529) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1758578559 + ... + 1758701521.

It is an arithmetic number, because the mean of its divisors is an integer number (3940458232500).

Almost surely, 2^{216247655238520} is an apocalyptic number.

216247655238520 is a gapful number since it is divisible by the number (20) 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 216247655238520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (252189326880000).

216247655238520 is an abundant number, since it is smaller than the sum of its proper divisors (288130998521480).

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

216247655238520 is a wasteful number, since it uses less digits than its factorization.

216247655238520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126133 (or 126129 counting only the distinct ones).

The product of its (nonzero) digits is 48384000, while the sum is 58.

The spelling of 216247655238520 in words is "two hundred sixteen trillion, two hundred forty-seven billion, six hundred fifty-five million, two hundred thirty-eight thousand, five hundred twenty".