221966525 has 12 divisors (see below), whose sum is σ = 300260544. Its totient is φ = 161430000.

The previous prime is 221966509. The next prime is 221966533. The reversal of 221966525 is 525669122.

It is not a de Polignac number, because 221966525 - 2⁴ = 221966509 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 403301 + ... + 403850.

It is an arithmetic number, because the mean of its divisors is an integer number (25021712).

Almost surely, 2^221966525 is an apocalyptic number.

221966525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

221966525 is a deficient number, since it is larger than the sum of its proper divisors (78294019).

221966525 is a wasteful number, since it uses less digits than its factorization.

221966525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 807172 (or 807167 counting only the distinct ones).

The product of its digits is 64800, while the sum is 38.

The square root of 221966525 is about 14898.5410359538. The cubic root of 221966525 is about 605.4744587724.

The spelling of 221966525 in words is "two hundred twenty-one million, nine hundred sixty-six thousand, five hundred twenty-five".