21021021202 has 4 divisors (see below), whose sum is σ = 31531531806. Its totient is φ = 10510510600.

The previous prime is 21021021199. The next prime is 21021021269. The reversal of 21021021202 is 20212012012.

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., 18219330441 + 2801690761 = 134979^2 + 52931^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5255255299 + ... + 5255255302.

Almost surely, 2^21021021202 is an apocalyptic number.

21021021202 is a deficient number, since it is larger than the sum of its proper divisors (10510510604).

21021021202 is a wasteful number, since it uses less digits than its factorization.

21021021202 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10510510603.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21021021202 its reverse (20212012012), we get a palindrome (41233033214).

The spelling of 21021021202 in words is "twenty-one billion, twenty-one million, twenty-one thousand, two hundred two".