221161212 has 48 divisors (see below), whose sum is σ = 586727680. Its totient is φ = 72004464.

The previous prime is 221161201. The next prime is 221161231. The reversal of 221161212 is 212161122.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a nude number because it is divisible by every one of its digits.

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 15 ways as a sum of consecutive naturals, for example, 19168 + ... + 28455.

Almost surely, 2^221161212 is an apocalyptic number.

It is an amenable number.

221161212 is an abundant number, since it is smaller than the sum of its proper divisors (365566468).

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

221161212 is a wasteful number, since it uses less digits than its factorization.

221161212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47679 (or 47671 counting only the distinct ones).

The product of its digits is 96, while the sum is 18.

The square root of 221161212 is about 14871.4899051843. The cubic root of 221161212 is about 604.7413342252.

The spelling of 221161212 in words is "two hundred twenty-one million, one hundred sixty-one thousand, two hundred twelve".