21122012 has 6 divisors (see below), whose sum is σ = 36963528. Its totient is φ = 10561004.

The previous prime is 21122009. The next prime is 21122033. The reversal of 21122012 is 21022112.

It is a happy number.

It is a super-2 number, since 2×21122012² = 892278781856288, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21121984 and 21122002.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2640248 + ... + 2640255.

It is an arithmetic number, because the mean of its divisors is an integer number (6160588).

Almost surely, 2^21122012 is an apocalyptic number.

It is an amenable number.

21122012 is a deficient number, since it is larger than the sum of its proper divisors (15841516).

21122012 is a wasteful number, since it uses less digits than its factorization.

21122012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5280507 (or 5280505 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 21122012 is about 4595.8690146696. The cubic root of 21122012 is about 276.4257065553.

Adding to 21122012 its reverse (21022112), we get a palindrome (42144124).

The spelling of 21122012 in words is "twenty-one million, one hundred twenty-two thousand, twelve".