21404333425 has 12 divisors (see below), whose sum is σ = 26559126000. Its totient is φ = 17112013520.

The previous prime is 21404333411. The next prime is 21404333437. The reversal of 21404333425 is 52433340412.

It is a happy number.

It is not a de Polignac number, because 21404333425 - 2²⁵ = 21370778993 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 248107 + ... + 323056.

It is an arithmetic number, because the mean of its divisors is an integer number (2213260500).

Almost surely, 2^21404333425 is an apocalyptic number.

21404333425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21404333425 is a deficient number, since it is larger than the sum of its proper divisors (5154792575).

21404333425 is a wasteful number, since it uses less digits than its factorization.

21404333425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 572672 (or 572667 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 31.

Adding to 21404333425 its reverse (52433340412), we get a palindrome (73837673837).

The spelling of 21404333425 in words is "twenty-one billion, four hundred four million, three hundred thirty-three thousand, four hundred twenty-five".