21305404002 has 16 divisors (see below), whose sum is σ = 42623028000. Its totient is φ = 7099764672.

The previous prime is 21305403991. The next prime is 21305404009. The reversal of 21305404002 is 20040450312.

It is a self number, because there is not a number n which added to its sum of digits gives 21305404002.

It is not an unprimeable number, because it can be changed into a prime (21305404009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 486423 + ... + 528410.

It is an arithmetic number, because the mean of its divisors is an integer number (2663939250).

Almost surely, 2^21305404002 is an apocalyptic number.

21305404002 is an abundant number, since it is smaller than the sum of its proper divisors (21317623998).

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

21305404002 is a wasteful number, since it uses less digits than its factorization.

21305404002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1018337.

The product of its (nonzero) digits is 960, while the sum is 21.

Adding to 21305404002 its reverse (20040450312), we get a palindrome (41345854314).

The spelling of 21305404002 in words is "twenty-one billion, three hundred five million, four hundred four thousand, two".