21405425001 has 8 divisors (see below), whose sum is σ = 28823146944. Its totient is φ = 14128993200.

The previous prime is 21405424969. The next prime is 21405425009. The reversal of 21405425001 is 10052450412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21405425001 - 2⁵ = 21405424969 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21405425009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35322181 + ... + 35322786.

It is an arithmetic number, because the mean of its divisors is an integer number (3602893368).

Almost surely, 2^21405425001 is an apocalyptic number.

It is an amenable number.

21405425001 is a deficient number, since it is larger than the sum of its proper divisors (7417721943).

21405425001 is a wasteful number, since it uses less digits than its factorization.

21405425001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70645071.

The product of its (nonzero) digits is 1600, while the sum is 24.

Adding to 21405425001 its reverse (10052450412), we get a palindrome (31457875413).

The spelling of 21405425001 in words is "twenty-one billion, four hundred five million, four hundred twenty-five thousand, one".