216899640 has 128 divisors (see below), whose sum is σ = 726984000. Its totient is φ = 57521664.

The previous prime is 216899609. The next prime is 216899647. The reversal of 216899640 is 46998612.

It is a happy number.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216899647) 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 31 ways as a sum of consecutive naturals, for example, 246882 + ... + 247758.

Almost surely, 2^216899640 is an apocalyptic number.

216899640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216899640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (363492000).

216899640 is an abundant number, since it is smaller than the sum of its proper divisors (510084360).

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

216899640 is a wasteful number, since it uses less digits than its factorization.

216899640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1126 (or 1116 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The square root of 216899640 is about 14727.5130283426. The cubic root of 216899640 is about 600.8318461869.

It can be divided in two parts, 21689 and 9640, that added together give a square (31329 = 177²).

The spelling of 216899640 in words is "two hundred sixteen million, eight hundred ninety-nine thousand, six hundred forty".