21022001004 has 24 divisors (see below), whose sum is σ = 49297830400. Its totient is φ = 6972120144.

The previous prime is 21022000903. The next prime is 21022001029. The reversal of 21022001004 is 40010022012.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4399204 + ... + 4403979.

Almost surely, 2^21022001004 is an apocalyptic number.

It is an amenable number.

21022001004 is an abundant number, since it is smaller than the sum of its proper divisors (28275829396).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21022001004 is a wasteful number, since it uses less digits than its factorization.

21022001004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8803389 (or 8803387 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

Adding to 21022001004 its reverse (40010022012), we get a palindrome (61032023016).

The spelling of 21022001004 in words is "twenty-one billion, twenty-two million, one thousand, four".