21641260025 has 48 divisors (see below), whose sum is σ = 33833013120. Its totient is φ = 13338969600.

The previous prime is 21641260021. The next prime is 21641260061. The reversal of 21641260025 is 52006214612.

It is not a de Polignac number, because 21641260025 - 2² = 21641260021 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21641260025.

It is not an unprimeable number, because it can be changed into a prime (21641260021) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 108167 + ... + 234483.

It is an arithmetic number, because the mean of its divisors is an integer number (704854440).

Almost surely, 2^21641260025 is an apocalyptic number.

21641260025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21641260025 is a deficient number, since it is larger than the sum of its proper divisors (12191753095).

21641260025 is a wasteful number, since it uses less digits than its factorization.

21641260025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126434 (or 126429 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 29.

Adding to 21641260025 its reverse (52006214612), we get a palindrome (73647474637).

The spelling of 21641260025 in words is "twenty-one billion, six hundred forty-one million, two hundred sixty thousand, twenty-five".