21103212007 has 2 divisors, whose sum is σ = 21103212008. Its totient is φ = 21103212006.

The previous prime is 21103211999. The next prime is 21103212041. The reversal of 21103212007 is 70021230112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21103212007 - 2³ = 21103211999 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21103212077) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10551606003 + 10551606004.

It is an arithmetic number, because the mean of its divisors is an integer number (10551606004).

Almost surely, 2^21103212007 is an apocalyptic number.

21103212007 is a deficient number, since it is larger than the sum of its proper divisors (1).

21103212007 is an equidigital number, since it uses as much as digits as its factorization.

21103212007 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 168, while the sum is 19.

Adding to 21103212007 its reverse (70021230112), we get a palindrome (91124442119).

The spelling of 21103212007 in words is "twenty-one billion, one hundred three million, two hundred twelve thousand, seven".