21000020204 has 6 divisors (see below), whose sum is σ = 36750035364. Its totient is φ = 10500010100.

The previous prime is 21000020201. The next prime is 21000020221. The reversal of 21000020204 is 40202000012.

It is not an unprimeable number, because it can be changed into a prime (21000020201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2625002522 + ... + 2625002529.

It is an arithmetic number, because the mean of its divisors is an integer number (6125005894).

Almost surely, 2^21000020204 is an apocalyptic number.

It is an amenable number.

21000020204 is a deficient number, since it is larger than the sum of its proper divisors (15750015160).

21000020204 is a wasteful number, since it uses less digits than its factorization.

21000020204 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5250005055 (or 5250005053 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 11.

Adding to 21000020204 its reverse (40202000012), we get a palindrome (61202020216).

The spelling of 21000020204 in words is "twenty-one billion, twenty thousand, two hundred four".