21011221202 has 4 divisors (see below), whose sum is σ = 31516831806. Its totient is φ = 10505610600.

The previous prime is 21011221181. The next prime is 21011221223. The reversal of 21011221202 is 20212211012.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (21011221181) and next prime (21011221223).

It can be written as a sum of positive squares in only one way, i.e., 17444862241 + 3566358961 = 132079^2 + 59719^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5252805299 + ... + 5252805302.

Almost surely, 2^21011221202 is an apocalyptic number.

21011221202 is a deficient number, since it is larger than the sum of its proper divisors (10505610604).

21011221202 is a wasteful number, since it uses less digits than its factorization.

21011221202 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10505610603.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21011221202 its reverse (20212211012), we get a palindrome (41223432214).

The spelling of 21011221202 in words is "twenty-one billion, eleven million, two hundred twenty-one thousand, two hundred two".