268640220 has 24 divisors (see below), whose sum is σ = 752192784. Its totient is φ = 71637376.

The previous prime is 268640209. The next prime is 268640243. The reversal of 268640220 is 22046862.

268640220 = 2572² + 2573² + ... + 2611².

It is a super-3 number, since 3×268640220³ (a number of 26 digits) contains 333 as substring.

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

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 2238609 + ... + 2238728.

It is an arithmetic number, because the mean of its divisors is an integer number (31341366).

Almost surely, 2^268640220 is an apocalyptic number.

268640220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

268640220 is an abundant number, since it is smaller than the sum of its proper divisors (483552564).

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

268640220 is a wasteful number, since it uses less digits than its factorization.

268640220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4477349 (or 4477347 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 30.

The square root of 268640220 is about 16390.2477101476. The cubic root of 268640220 is about 645.2435592406.

The spelling of 268640220 in words is "two hundred sixty-eight million, six hundred forty thousand, two hundred twenty".