216446566251 has 4 divisors (see below), whose sum is σ = 288595421672. Its totient is φ = 144297710832.

The previous prime is 216446566247. The next prime is 216446566313. The reversal of 216446566251 is 152665644612.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 216446566251 - 2² = 216446566247 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 216446566251.

It is not an unprimeable number, because it can be changed into a prime (216446566211) 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, 36074427706 + ... + 36074427711.

It is an arithmetic number, because the mean of its divisors is an integer number (72148855418).

Almost surely, 2^216446566251 is an apocalyptic number.

216446566251 is a deficient number, since it is larger than the sum of its proper divisors (72148855421).

216446566251 is an equidigital number, since it uses as much as digits as its factorization.

216446566251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72148855420.

The product of its digits is 2073600, while the sum is 48.

The spelling of 216446566251 in words is "two hundred sixteen billion, four hundred forty-six million, five hundred sixty-six thousand, two hundred fifty-one".