216815682828680 has 128 divisors (see below), whose sum is σ = 525846126808800. Its totient is φ = 79981134815232.

The previous prime is 216815682828677. The next prime is 216815682828799. The reversal of 216815682828680 is 86828286518612.

It can be written as a sum of positive squares in 16 ways, for example, as 1491578575204 + 215324104253476 = 1221302^2 + 14673926^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3568540862 + ... + 3568601618.

Almost surely, 2^{216815682828680} is an apocalyptic number.

216815682828680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216815682828680 is an abundant number, since it is smaller than the sum of its proper divisors (309030443980120).

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

216815682828680 is a wasteful number, since it uses less digits than its factorization.

216815682828680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67003 (or 66999 counting only the distinct ones).

The product of its (nonzero) digits is 283115520, while the sum is 71.

The spelling of 216815682828680 in words is "two hundred sixteen trillion, eight hundred fifteen billion, six hundred eighty-two million, eight hundred twenty-eight thousand, six hundred eighty".