221202645 has 16 divisors (see below), whose sum is σ = 354111360. Its totient is φ = 117912384.

The previous prime is 221202581. The next prime is 221202659. The reversal of 221202645 is 546202122.

It is a happy number.

It is not a de Polignac number, because 221202645 - 2⁶ = 221202581 is a prime.

It is a super-2 number, since 2×221202645² = 97861220309992050, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 46152 + ... + 50718.

It is an arithmetic number, because the mean of its divisors is an integer number (22131960).

Almost surely, 2^221202645 is an apocalyptic number.

It is an amenable number.

221202645 is a deficient number, since it is larger than the sum of its proper divisors (132908715).

221202645 is a wasteful number, since it uses less digits than its factorization.

221202645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7804.

The product of its (nonzero) digits is 1920, while the sum is 24.

The square root of 221202645 is about 14872.8828745472. The cubic root of 221202645 is about 604.7790965479.

Adding to 221202645 its reverse (546202122), we get a palindrome (767404767).

The spelling of 221202645 in words is "two hundred twenty-one million, two hundred two thousand, six hundred forty-five".