21102032121 has 4 divisors (see below), whose sum is σ = 28136042832. Its totient is φ = 14068021412.

The previous prime is 21102032117. The next prime is 21102032123. The reversal of 21102032121 is 12123020112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21102032121 - 2² = 21102032117 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21102032121.

It is not an unprimeable number, because it can be changed into a prime (21102032123) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3517005351 + ... + 3517005356.

It is an arithmetic number, because the mean of its divisors is an integer number (7034010708).

Almost surely, 2^21102032121 is an apocalyptic number.

It is an amenable number.

21102032121 is a deficient number, since it is larger than the sum of its proper divisors (7034010711).

21102032121 is an equidigital number, since it uses as much as digits as its factorization.

21102032121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7034010710.

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 21102032121 its reverse (12123020112), we get a palindrome (33225052233).

The spelling of 21102032121 in words is "twenty-one billion, one hundred two million, thirty-two thousand, one hundred twenty-one".