216220545657646 has 8 divisors (see below), whose sum is σ = 324370775492280. Its totient is φ = 108096953826888.

The previous prime is 216220545657643. The next prime is 216220545657707. The reversal of 216220545657646 is 646756545022612.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×216220545657646² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216220545657643) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6659480676 + ... + 6659513143.

It is an arithmetic number, because the mean of its divisors is an integer number (40546346936535).

Almost surely, 2^{216220545657646} is an apocalyptic number.

216220545657646 is a deficient number, since it is larger than the sum of its proper divisors (108150229834634).

216220545657646 is a wasteful number, since it uses less digits than its factorization.

216220545657646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13319001938.

The product of its (nonzero) digits is 145152000, while the sum is 61.

The spelling of 216220545657646 in words is "two hundred sixteen trillion, two hundred twenty billion, five hundred forty-five million, six hundred fifty-seven thousand, six hundred forty-six".