21402404004 has 24 divisors (see below), whose sum is σ = 52567308640. Its totient is φ = 6758653824.

The previous prime is 21402404003. The next prime is 21402404011. The reversal of 21402404004 is 40040420412.

It is not an unprimeable number, because it can be changed into a prime (21402404003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 46934869 + ... + 46935324.

Almost surely, 2^21402404004 is an apocalyptic number.

It is an amenable number.

21402404004 is an abundant number, since it is smaller than the sum of its proper divisors (31164904636).

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

21402404004 is a wasteful number, since it uses less digits than its factorization.

21402404004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93870219 (or 93870217 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 21.

Adding to 21402404004 its reverse (40040420412), we get a palindrome (61442824416).

The spelling of 21402404004 in words is "twenty-one billion, four hundred two million, four hundred four thousand, four".