21700012 has 6 divisors (see below), whose sum is σ = 37975028. Its totient is φ = 10850004.

The previous prime is 21700001. The next prime is 21700039. The reversal of 21700012 is 21000712.

It is a junction number, because it is equal to n+sod(n) for n = 21699965 and 21700001.

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 as a sum of consecutive naturals, namely, 2712498 + ... + 2712505.

Almost surely, 2^21700012 is an apocalyptic number.

It is an amenable number.

21700012 is a deficient number, since it is larger than the sum of its proper divisors (16275016).

21700012 is a wasteful number, since it uses less digits than its factorization.

21700012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5425007 (or 5425005 counting only the distinct ones).

The product of its (nonzero) digits is 28, while the sum is 13.

The square root of 21700012 is about 4658.3271675570. The cubic root of 21700012 is about 278.9244966401.

Adding to 21700012 its reverse (21000712), we get a palindrome (42700724).

The spelling of 21700012 in words is "twenty-one million, seven hundred thousand, twelve".