216122445 has 128 divisors (see below), whose sum is σ = 507617280. Its totient is φ = 84464640.

The previous prime is 216122443. The next prime is 216122461. The reversal of 216122445 is 544221612.

216122445 is a `hidden beast` number, since 2 + 1 + 612 + 2 + 4 + 45 = 666.

216122445 is a nontrivial binomial coefficient, being equal to C(20791, 2).

It is not a de Polignac number, because 216122445 - 2¹ = 216122443 is a prime.

It is a super-2 number, since 2×216122445² = 93417822465556050, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216122441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 176104 + ... + 177326.

It is an arithmetic number, because the mean of its divisors is an integer number (3965760).

Almost surely, 2^216122445 is an apocalyptic number.

216122445 is the 20790-th triangular number.

It is an amenable number.

216122445 is an abundant number, since it is smaller than the sum of its proper divisors (291494835).

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

216122445 is a wasteful number, since it uses less digits than its factorization.

216122445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1272 (or 1266 counting only the distinct ones).

The product of its digits is 3840, while the sum is 27.

The square root of 216122445 is about 14701.1035300075. The cubic root of 216122445 is about 600.1133535836.

The spelling of 216122445 in words is "two hundred sixteen million, one hundred twenty-two thousand, four hundred forty-five".