21040020104 has 32 divisors (see below), whose sum is σ = 40604027520. Its totient is φ = 10213511616.

The previous prime is 21040020041. The next prime is 21040020107. The reversal of 21040020104 is 40102004012.

It is not an unprimeable number, because it can be changed into a prime (21040020107) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 60287 + ... + 213809.

It is an arithmetic number, because the mean of its divisors is an integer number (1268875860).

Almost surely, 2^21040020104 is an apocalyptic number.

It is an amenable number.

21040020104 is a deficient number, since it is larger than the sum of its proper divisors (19564007416).

21040020104 is a wasteful number, since it uses less digits than its factorization.

21040020104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154029 (or 154025 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 21040020104 its reverse (40102004012), we get a palindrome (61142024116).

The spelling of 21040020104 in words is "twenty-one billion, forty million, twenty thousand, one hundred four".