21213244404 has 72 divisors (see below), whose sum is σ = 58536354240. Its totient is φ = 6423945600.

The previous prime is 21213244369. The next prime is 21213244421. The reversal of 21213244404 is 40444231212.

21213244404 is a `hidden beast` number, since 2 + 1 + 2 + 13 + 244 + 404 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 600184 + ... + 634544.

It is an arithmetic number, because the mean of its divisors is an integer number (813004920).

Almost surely, 2^21213244404 is an apocalyptic number.

It is an amenable number.

21213244404 is an abundant number, since it is smaller than the sum of its proper divisors (37323109836).

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

21213244404 is a wasteful number, since it uses less digits than its factorization.

21213244404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35941 (or 35936 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 27.

Adding to 21213244404 its reverse (40444231212), we get a palindrome (61657475616).

The spelling of 21213244404 in words is "twenty-one billion, two hundred thirteen million, two hundred forty-four thousand, four hundred four".