21004221335125 has 64 divisors (see below), whose sum is σ = 30070861516800. Its totient is φ = 14348668276800.

The previous prime is 21004221335107. The next prime is 21004221335147. The reversal of 21004221335125 is 52153312240012.

It is a happy number.

It is not a de Polignac number, because 21004221335125 - 2⁵ = 21004221335093 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1574640706 + ... + 1574654044.

It is an arithmetic number, because the mean of its divisors is an integer number (469857211200).

Almost surely, 2^{21004221335125} is an apocalyptic number.

21004221335125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21004221335125 is a deficient number, since it is larger than the sum of its proper divisors (9066640181675).

21004221335125 is a wasteful number, since it uses less digits than its factorization.

21004221335125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20003 (or 19993 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 31.

Adding to 21004221335125 its reverse (52153312240012), we get a palindrome (73157533575137).

The spelling of 21004221335125 in words is "twenty-one trillion, four billion, two hundred twenty-one million, three hundred thirty-five thousand, one hundred twenty-five".