21012221012 has 24 divisors (see below), whose sum is σ = 37547256936. Its totient is φ = 10286535168.

The previous prime is 21012220969. The next prime is 21012221047.

21012221012 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 4 ways, for example, as 10313214916 + 10699006096 = 101554^2 + 103436^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 222623 + ... + 302630.

It is an arithmetic number, because the mean of its divisors is an integer number (1564469039).

Almost surely, 2^21012221012 is an apocalyptic number.

It is an amenable number.

21012221012 is a deficient number, since it is larger than the sum of its proper divisors (16535035924).

21012221012 is a wasteful number, since it uses less digits than its factorization.

21012221012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 525467 (or 525465 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

The spelling of 21012221012 in words is "twenty-one billion, twelve million, two hundred twenty-one thousand, twelve".