21012213304 has 8 divisors (see below), whose sum is σ = 39397899960. Its totient is φ = 10506106648.

The previous prime is 21012213301. The next prime is 21012213307. The reversal of 21012213304 is 40331221012.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21012213301) and next prime (21012213307).

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21012213301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1313263324 + ... + 1313263339.

It is an arithmetic number, because the mean of its divisors is an integer number (4924737495).

Almost surely, 2^21012213304 is an apocalyptic number.

It is an amenable number.

21012213304 is a deficient number, since it is larger than the sum of its proper divisors (18385686656).

21012213304 is a wasteful number, since it uses less digits than its factorization.

21012213304 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2626526669 (or 2626526665 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 21012213304 its reverse (40331221012), we get a palindrome (61343434316).

The spelling of 21012213304 in words is "twenty-one billion, twelve million, two hundred thirteen thousand, three hundred four".