21010221002 has 4 divisors (see below), whose sum is σ = 31515331506. Its totient is φ = 10505110500.

The previous prime is 21010220999. The next prime is 21010221053. The reversal of 21010221002 is 20012201012.

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., 11272281241 + 9737939761 = 106171^2 + 98681^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5252555249 + ... + 5252555252.

Almost surely, 2^21010221002 is an apocalyptic number.

21010221002 is a deficient number, since it is larger than the sum of its proper divisors (10505110504).

21010221002 is a wasteful number, since it uses less digits than its factorization.

21010221002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10505110503.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21010221002 its reverse (20012201012), we get a palindrome (41022422014).

The spelling of 21010221002 in words is "twenty-one billion, ten million, two hundred twenty-one thousand, two".