21435221204 has 12 divisors (see below), whose sum is σ = 38039970528. Its totient is φ = 10566658200.

The previous prime is 21435221189. The next prime is 21435221267. The reversal of 21435221204 is 40212253412.

It is a super-4 number, since 4×21435221204⁴ (a number of 42 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37737782 + ... + 37738349.

It is an arithmetic number, because the mean of its divisors is an integer number (3169997544).

Almost surely, 2^21435221204 is an apocalyptic number.

It is an amenable number.

21435221204 is a deficient number, since it is larger than the sum of its proper divisors (16604749324).

21435221204 is a wasteful number, since it uses less digits than its factorization.

21435221204 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75476206 (or 75476204 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 26.

Adding to 21435221204 its reverse (40212253412), we get a palindrome (61647474616).

The spelling of 21435221204 in words is "twenty-one billion, four hundred thirty-five million, two hundred twenty-one thousand, two hundred four".