21344221425 has 48 divisors (see below), whose sum is σ = 37514473920. Its totient is φ = 10677600000.

The previous prime is 21344221411. The next prime is 21344221433. The reversal of 21344221425 is 52412244312.

It is a happy number.

It is not a de Polignac number, because 21344221425 - 2²⁶ = 21277112561 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21344221392 and 21344221401.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 69775 + ... + 218075.

It is an arithmetic number, because the mean of its divisors is an integer number (781551540).

Almost surely, 2^21344221425 is an apocalyptic number.

21344221425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21344221425 is a deficient number, since it is larger than the sum of its proper divisors (16170252495).

21344221425 is a wasteful number, since it uses less digits than its factorization.

21344221425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148434 (or 148429 counting only the distinct ones).

The product of its digits is 15360, while the sum is 30.

Adding to 21344221425 its reverse (52412244312), we get a palindrome (73756465737).

The spelling of 21344221425 in words is "twenty-one billion, three hundred forty-four million, two hundred twenty-one thousand, four hundred twenty-five".