221736852 has 30 divisors (see below), whose sum is σ = 579664778. Its totient is φ = 73912176.

The previous prime is 221736841. The next prime is 221736869. The reversal of 221736852 is 258637122.

It can be written as a sum of positive squares in only one way, i.e., 211004676 + 10732176 = 14526^2 + 3276^2 .

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

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 9 ways as a sum of consecutive naturals, for example, 341863 + ... + 342510.

Almost surely, 2^221736852 is an apocalyptic number.

It is an amenable number.

221736852 is an abundant number, since it is smaller than the sum of its proper divisors (357927926).

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

221736852 is a wasteful number, since it uses less digits than its factorization.

221736852 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 684389 (or 684378 counting only the distinct ones).

The product of its digits is 40320, while the sum is 36.

The square root of 221736852 is about 14890.8311386571. The cubic root of 221736852 is about 605.2655547105.

The spelling of 221736852 in words is "two hundred twenty-one million, seven hundred thirty-six thousand, eight hundred fifty-two".