221550020 has 12 divisors (see below), whose sum is σ = 465255084. Its totient is φ = 88620000.

The previous prime is 221550011. The next prime is 221550023. The reversal of 221550020 is 20055122.

It can be written as a sum of positive squares in 2 ways, for example, as 91087936 + 130462084 = 9544^2 + 11422^2 .

It is a super-2 number, since 2×221550020² = 98168822724000800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (221550023) 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 3 ways as a sum of consecutive naturals, for example, 5538731 + ... + 5538770.

It is an arithmetic number, because the mean of its divisors is an integer number (38771257).

Almost surely, 2^221550020 is an apocalyptic number.

221550020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221550020 is an abundant number, since it is smaller than the sum of its proper divisors (243705064).

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

221550020 is a wasteful number, since it uses less digits than its factorization.

221550020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11077510 (or 11077508 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 17.

The square root of 221550020 is about 14884.5564260411. The cubic root of 221550020 is about 605.0955111827.

The spelling of 221550020 in words is "two hundred twenty-one million, five hundred fifty thousand, twenty".