220644840 has 64 divisors (see below), whose sum is σ = 712857600. Its totient is φ = 54312192.

The previous prime is 220644839. The next prime is 220644841. The reversal of 220644840 is 48446022.

220644840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (220644839) and next prime (220644841).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 220644798 and 220644807.

It is not an unprimeable number, because it can be changed into a prime (220644841) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 69160 + ... + 72279.

It is an arithmetic number, because the mean of its divisors is an integer number (11138400).

Almost surely, 2^220644840 is an apocalyptic number.

220644840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

220644840 is an abundant number, since it is smaller than the sum of its proper divisors (492212760).

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

220644840 is a wasteful number, since it uses less digits than its factorization.

220644840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141466 (or 141462 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 30.

The square root of 220644840 is about 14854.1186207732. The cubic root of 220644840 is about 604.2703130518.

The spelling of 220644840 in words is "two hundred twenty million, six hundred forty-four thousand, eight hundred forty".