216561212050 has 48 divisors (see below), whose sum is σ = 417629912832. Its totient is φ = 83460715200.

The previous prime is 216561211961. The next prime is 216561212053. The reversal of 216561212050 is 50212165612.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is not an unprimeable number, because it can be changed into a prime (216561212053) 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, 44104 + ... + 659596.

It is an arithmetic number, because the mean of its divisors is an integer number (8700623184).

Almost surely, 2^216561212050 is an apocalyptic number.

216561212050 is a deficient number, since it is larger than the sum of its proper divisors (201068700782).

216561212050 is a wasteful number, since it uses less digits than its factorization.

216561212050 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 615763 (or 615758 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 31.

Adding to 216561212050 its reverse (50212165612), we get a palindrome (266773377662).

The spelling of 216561212050 in words is "two hundred sixteen billion, five hundred sixty-one million, two hundred twelve thousand, fifty".