216664761672 has 24 divisors (see below), whose sum is σ = 586800396390. Its totient is φ = 72221587200.

The previous prime is 216664761661. The next prime is 216664761683. The reversal of 216664761672 is 276167466612.

It is an interprime number because it is at equal distance from previous prime (216664761661) and next prime (216664761683).

It can be written as a sum of positive squares in only one way, i.e., 216498506436 + 166255236 = 465294^2 + 12894^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1504616329 + ... + 1504616472.

Almost surely, 2^216664761672 is an apocalyptic number.

It is an amenable number.

216664761672 is an abundant number, since it is smaller than the sum of its proper divisors (370135634718).

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

216664761672 is a wasteful number, since it uses less digits than its factorization.

216664761672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3009232813 (or 3009232806 counting only the distinct ones).

The product of its digits is 6096384, while the sum is 54.

The spelling of 216664761672 in words is "two hundred sixteen billion, six hundred sixty-four million, seven hundred sixty-one thousand, six hundred seventy-two".