21021022202 has 4 divisors (see below), whose sum is σ = 31531533306. Its totient is φ = 10510511100.

The previous prime is 21021022171. The next prime is 21021022207. The reversal of 21021022202 is 20222012012.

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., 19510223041 + 1510799161 = 139679^2 + 38869^2 .

It is not an unprimeable number, because it can be changed into a prime (21021022207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5255255549 + ... + 5255255552.

Almost surely, 2^21021022202 is an apocalyptic number.

21021022202 is a deficient number, since it is larger than the sum of its proper divisors (10510511104).

21021022202 is a wasteful number, since it uses less digits than its factorization.

21021022202 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10510511103.

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 21021022202 its reverse (20222012012), we get a palindrome (41243034214).

The spelling of 21021022202 in words is "twenty-one billion, twenty-one million, twenty-two thousand, two hundred two".