221814825 has 12 divisors (see below), whose sum is σ = 366733968. Its totient is φ = 118301200.

The previous prime is 221814821. The next prime is 221814851. The reversal of 221814825 is 528418122.

It is not a de Polignac number, because 221814825 - 2² = 221814821 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221814821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1478691 + ... + 1478840.

It is an arithmetic number, because the mean of its divisors is an integer number (30561164).

Almost surely, 2^221814825 is an apocalyptic number.

221814825 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

221814825 is a deficient number, since it is larger than the sum of its proper divisors (144919143).

221814825 is a wasteful number, since it uses less digits than its factorization.

221814825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2957544 (or 2957539 counting only the distinct ones).

The product of its digits is 10240, while the sum is 33.

The square root of 221814825 is about 14893.4490632627. The cubic root of 221814825 is about 605.3364929117.

The spelling of 221814825 in words is "two hundred twenty-one million, eight hundred fourteen thousand, eight hundred twenty-five".