21212074 has 16 divisors (see below), whose sum is σ = 34358688. Its totient is φ = 9763632.

The previous prime is 21212071. The next prime is 21212077. The reversal of 21212074 is 47021212.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21212071) and next prime (21212077).

It is not an unprimeable number, because it can be changed into a prime (21212071) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 11269 + ... + 13015.

It is an arithmetic number, because the mean of its divisors is an integer number (2147418).

Almost surely, 2^21212074 is an apocalyptic number.

21212074 is a deficient number, since it is larger than the sum of its proper divisors (13146614).

21212074 is a wasteful number, since it uses less digits than its factorization.

21212074 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2229.

The product of its (nonzero) digits is 224, while the sum is 19.

The square root of 21212074 is about 4605.6567392718. The cubic root of 21212074 is about 276.8180326859.

Adding to 21212074 its reverse (47021212), we get a palindrome (68233286).

The spelling of 21212074 in words is "twenty-one million, two hundred twelve thousand, seventy-four".