21021012112 has 10 divisors (see below), whose sum is σ = 40728210998. Its totient is φ = 10510506048.

The previous prime is 21021012109. The next prime is 21021012139. The reversal of 21021012112 is 21121012012.

It can be written as a sum of positive squares in only one way, i.e., 20711815056 + 309197056 = 143916^2 + 17584^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21021012092 and 21021012101.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 656906613 + ... + 656906644.

Almost surely, 2^21021012112 is an apocalyptic number.

It is an amenable number.

21021012112 is a deficient number, since it is larger than the sum of its proper divisors (19707198886).

21021012112 is a wasteful number, since it uses less digits than its factorization.

21021012112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1313813265 (or 1313813259 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21021012112 its reverse (21121012012), we get a palindrome (42142024124).

The spelling of 21021012112 in words is "twenty-one billion, twenty-one million, twelve thousand, one hundred twelve".