21021002012 has 12 divisors (see below), whose sum is σ = 36933316056. Its totient is φ = 10468626000.

The previous prime is 21021002003. The next prime is 21021002087. The reversal of 21021002012 is 21020012012.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21021001984 and 21021002002.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10467623 + ... + 10469630.

It is an arithmetic number, because the mean of its divisors is an integer number (3077776338).

Almost surely, 2^21021002012 is an apocalyptic number.

It is an amenable number.

21021002012 is a deficient number, since it is larger than the sum of its proper divisors (15912314044).

21021002012 is a wasteful number, since it uses less digits than its factorization.

21021002012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20937508 (or 20937506 counting only the distinct ones).

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

Adding to 21021002012 its reverse (21020012012), we get a palindrome (42041014024).

The spelling of 21021002012 in words is "twenty-one billion, twenty-one million, two thousand, twelve".