21234043404 has 120 divisors (see below), whose sum is σ = 63861143808. Its totient is φ = 6026594400.

The previous prime is 21234043399. The next prime is 21234043421. The reversal of 21234043404 is 40434043212.

It is a happy number.

21234043404 is a `hidden beast` number, since 21 + 234 + 0 + 4 + 3 + 404 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 311467 + ... + 373469.

Almost surely, 2^21234043404 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21234043404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31930571904).

21234043404 is an abundant number, since it is smaller than the sum of its proper divisors (42627100404).

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

21234043404 is a wasteful number, since it uses less digits than its factorization.

21234043404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62177 (or 62166 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 27.

Adding to 21234043404 its reverse (40434043212), we get a palindrome (61668086616).

The spelling of 21234043404 in words is "twenty-one billion, two hundred thirty-four million, forty-three thousand, four hundred four".