21002102210121 has 8 divisors (see below), whose sum is σ = 28004243423904. Its totient is φ = 14000681234880.

The previous prime is 21002102210113. The next prime is 21002102210137. The reversal of 21002102210121 is 12101220120012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21002102210121 - 2³ = 21002102210113 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21002102210121.

It is not an unprimeable number, because it can be changed into a prime (21002102210171) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 179991591 + ... + 180108236.

It is an arithmetic number, because the mean of its divisors is an integer number (3500530427988).

Almost surely, 2^{21002102210121} is an apocalyptic number.

It is an amenable number.

21002102210121 is a deficient number, since it is larger than the sum of its proper divisors (7002141213783).

21002102210121 is a wasteful number, since it uses less digits than its factorization.

21002102210121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 360119271.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21002102210121 its reverse (12101220120012), we get a palindrome (33103322330133).

The spelling of 21002102210121 in words is "twenty-one trillion, two billion, one hundred two million, two hundred ten thousand, one hundred twenty-one".