221552541 has 24 divisors (see below), whose sum is σ = 366135744. Its totient is φ = 126463680.

The previous prime is 221552519. The next prime is 221552543. The reversal of 221552541 is 145255122.

It is not a de Polignac number, because 221552541 - 2²² = 217358237 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221552543) 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 23 ways as a sum of consecutive naturals, for example, 95305 + ... + 97601.

It is an arithmetic number, because the mean of its divisors is an integer number (15255656).

Almost surely, 2^221552541 is an apocalyptic number.

221552541 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

221552541 is a deficient number, since it is larger than the sum of its proper divisors (144583203).

221552541 is a wasteful number, since it uses less digits than its factorization.

221552541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3841 (or 3838 counting only the distinct ones).

The product of its digits is 4000, while the sum is 27.

The square root of 221552541 is about 14884.6411108901. The cubic root of 221552541 is about 605.0978062852.

It can be divided in two parts, 2215 and 52541, that added together give a square (54756 = 234²).

The spelling of 221552541 in words is "two hundred twenty-one million, five hundred fifty-two thousand, five hundred forty-one".