21102012002 has 4 divisors (see below), whose sum is σ = 31653018006. Its totient is φ = 10551006000.

The previous prime is 21102011999. The next prime is 21102012031. The reversal of 21102012002 is 20021020112.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 17226825001 + 3875187001 = 131251^2 + 62251^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5275502999 + ... + 5275503002.

Almost surely, 2^21102012002 is an apocalyptic number.

21102012002 is a deficient number, since it is larger than the sum of its proper divisors (10551006004).

21102012002 is a wasteful number, since it uses less digits than its factorization.

21102012002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10551006003.

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

Adding to 21102012002 its reverse (20021020112), we get a palindrome (41123032114).

The spelling of 21102012002 in words is "twenty-one billion, one hundred two million, twelve thousand, two".