216725790 has 64 divisors (see below), whose sum is σ = 529182720. Its totient is φ = 56799360.

The previous prime is 216725779. The next prime is 216725797. The reversal of 216725790 is 97527612.

216725790 is a nontrivial binomial coefficient, being equal to C(20820, 2).

It is a super-2 number, since 2×216725790² = 93940136102248200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216725797) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 624397 + ... + 624743.

It is an arithmetic number, because the mean of its divisors is an integer number (8268480).

Almost surely, 2^216725790 is an apocalyptic number.

216725790 is the 20819-th triangular number and also the 10410-th hexagonal number.

216725790 is an abundant number, since it is smaller than the sum of its proper divisors (312456930).

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

216725790 is a wasteful number, since it uses less digits than its factorization.

216725790 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 657.

The product of its (nonzero) digits is 52920, while the sum is 39.

The square root of 216725790 is about 14721.6096266679. The cubic root of 216725790 is about 600.6712764775.

The spelling of 216725790 in words is "two hundred sixteen million, seven hundred twenty-five thousand, seven hundred ninety".