21006259641 has 24 divisors (see below), whose sum is σ = 30912485760. Its totient is φ = 13741904736.

The previous prime is 21006259607. The next prime is 21006259709. The reversal of 21006259641 is 14695260012.

21006259641 is a `hidden beast` number, since 2 + 1 + 0 + 0 + 6 + 2 + 5 + 9 + 641 = 666.

It is not a de Polignac number, because 21006259641 - 2⁶ = 21006259577 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21006259596 and 21006259605.

It is not an unprimeable number, because it can be changed into a prime (21006259441) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 260256 + ... + 331278.

It is an arithmetic number, because the mean of its divisors is an integer number (1288020240).

Almost surely, 2^21006259641 is an apocalyptic number.

It is an amenable number.

21006259641 is a deficient number, since it is larger than the sum of its proper divisors (9906226119).

21006259641 is a wasteful number, since it uses less digits than its factorization.

21006259641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71645 (or 71642 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The spelling of 21006259641 in words is "twenty-one billion, six million, two hundred fifty-nine thousand, six hundred forty-one".