21021210121202 has 4 divisors (see below), whose sum is σ = 31531815181806. Its totient is φ = 10510605060600.

The previous prime is 21021210121187. The next prime is 21021210121237. The reversal of 21021210121202 is 20212101212012.

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., 20806999437961 + 214210683241 = 4561469^2 + 462829^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5255302530299 + ... + 5255302530302.

Almost surely, 2^{21021210121202} is an apocalyptic number.

21021210121202 is a deficient number, since it is larger than the sum of its proper divisors (10510605060604).

21021210121202 is a wasteful number, since it uses less digits than its factorization.

21021210121202 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10510605060603.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21021210121202 its reverse (20212101212012), we get a palindrome (41233311333214).

The spelling of 21021210121202 in words is "twenty-one trillion, twenty-one billion, two hundred ten million, one hundred twenty-one thousand, two hundred two".