21220002 has 16 divisors (see below), whose sum is σ = 47155680. Its totient is φ = 7073316.

The previous prime is 21219997. The next prime is 21220019. The reversal of 21220002 is 20002212.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 196428 + ... + 196535.

It is an arithmetic number, because the mean of its divisors is an integer number (2947230).

Almost surely, 2^21220002 is an apocalyptic number.

21220002 is an abundant number, since it is smaller than the sum of its proper divisors (25935678).

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

21220002 is a wasteful number, since it uses less digits than its factorization.

21220002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392974 (or 392968 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

The square root of 21220002 is about 4606.5173395962. The cubic root of 21220002 is about 276.8525152485.

Adding to 21220002 its reverse (20002212), we get a palindrome (41222214).

It can be divided in two parts, 212 and 20002, that multiplied together give a palindrome (4240424).

The spelling of 21220002 in words is "twenty-one million, two hundred twenty thousand, two".