216122640 has 40 divisors (see below), whose sum is σ = 669980928. Its totient is φ = 57632640.

The previous prime is 216122639. The next prime is 216122653. The reversal of 216122640 is 46221612.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 216122640.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 450016 + ... + 450495.

Almost surely, 2^216122640 is an apocalyptic number.

216122640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216122640 is an abundant number, since it is smaller than the sum of its proper divisors (453858288).

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

216122640 is a wasteful number, since it uses less digits than its factorization.

216122640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 900527 (or 900521 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 216122640 is about 14701.1101621612. The cubic root of 216122640 is about 600.1135340709.

The spelling of 216122640 in words is "two hundred sixteen million, one hundred twenty-two thousand, six hundred forty".