21002122312 has 32 divisors (see below), whose sum is σ = 39573101880. Its totient is φ = 10449354240.

The previous prime is 21002122301. The next prime is 21002122381. The reversal of 21002122312 is 21322120012.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 18614236356 + 2387885956 = 136434^2 + 48866^2 .

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 in 7 ways as a sum of consecutive naturals, for example, 4361218 + ... + 4366030.

Almost surely, 2^21002122312 is an apocalyptic number.

It is an amenable number.

21002122312 is a deficient number, since it is larger than the sum of its proper divisors (18570979568).

21002122312 is a wasteful number, since it uses less digits than its factorization.

21002122312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7393 (or 7389 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 21002122312 its reverse (21322120012), we get a palindrome (42324242324).

The spelling of 21002122312 in words is "twenty-one billion, two million, one hundred twenty-two thousand, three hundred twelve".