228621820 has 48 divisors (see below), whose sum is σ = 550065600. Its totient is φ = 78188544.

The previous prime is 228621793. The next prime is 228621823. The reversal of 228621820 is 28126822.

It is a super-2 number, since 2×228621820² = 104535873160224800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (228621823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 61042 + ... + 64678.

It is an arithmetic number, because the mean of its divisors is an integer number (11459700).

Almost surely, 2^228621820 is an apocalyptic number.

228621820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

228621820 is an abundant number, since it is smaller than the sum of its proper divisors (321443780).

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

228621820 is a wasteful number, since it uses less digits than its factorization.

228621820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4102 (or 4100 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 31.

The square root of 228621820 is about 15120.2453683794. The cubic root of 228621820 is about 611.4663459957.

It can be divided in two parts, 228621 and 820, that added together give a square (229441 = 479²).

The spelling of 228621820 in words is "two hundred twenty-eight million, six hundred twenty-one thousand, eight hundred twenty".