21125132004 has 12 divisors (see below), whose sum is σ = 49291974704. Its totient is φ = 7041710664.

The previous prime is 21125132003. The next prime is 21125132033. The reversal of 21125132004 is 40023152112.

It is a tau number, because it is divible by the number of its divisors (12).

It is not an unprimeable number, because it can be changed into a prime (21125132003) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 880213822 + ... + 880213845.

Almost surely, 2^21125132004 is an apocalyptic number.

It is an amenable number.

21125132004 is an abundant number, since it is smaller than the sum of its proper divisors (28166842700).

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

21125132004 is a wasteful number, since it uses less digits than its factorization.

21125132004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1760427674 (or 1760427672 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

Adding to 21125132004 its reverse (40023152112), we get a palindrome (61148284116).

The spelling of 21125132004 in words is "twenty-one billion, one hundred twenty-five million, one hundred thirty-two thousand, four".