21356212704404 has 24 divisors (see below), whose sum is σ = 38998491786240. Its totient is φ = 10213791011424.

The previous prime is 21356212704371. The next prime is 21356212704433. The reversal of 21356212704404 is 40440721265312.

It is a super-2 number, since 2×21356212704404² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

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, 24276557 + ... + 25140875.

It is an arithmetic number, because the mean of its divisors is an integer number (1624937157760).

Almost surely, 2^{21356212704404} is an apocalyptic number.

It is an amenable number.

21356212704404 is a deficient number, since it is larger than the sum of its proper divisors (17642279081836).

21356212704404 is a wasteful number, since it uses less digits than its factorization.

21356212704404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1132919 (or 1132917 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 41.

Adding to 21356212704404 its reverse (40440721265312), we get a palindrome (61796933969716).

The spelling of 21356212704404 in words is "twenty-one trillion, three hundred fifty-six billion, two hundred twelve million, seven hundred four thousand, four hundred four".