221424012 has 36 divisors (see below), whose sum is σ = 568070776. Its totient is φ = 72705600.

The previous prime is 221424001. The next prime is 221424029. The reversal of 221424012 is 210424122.

221424012 is a `hidden beast` number, since 221 + 42 + 401 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×221424012² = 98057186180352288, which contains 22 as substring.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 43489 + ... + 48312.

Almost surely, 2^221424012 is an apocalyptic number.

It is an amenable number.

221424012 is an abundant number, since it is smaller than the sum of its proper divisors (346646764).

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

221424012 is a wasteful number, since it uses less digits than its factorization.

221424012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91878 (or 91873 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 221424012 is about 14880.3229803657. The cubic root of 221424012 is about 604.9807721048.

Adding to 221424012 its reverse (210424122), we get a palindrome (431848134).

The spelling of 221424012 in words is "two hundred twenty-one million, four hundred twenty-four thousand, twelve".