21241640456 has 8 divisors (see below), whose sum is σ = 39828075870. Its totient is φ = 10620820224.

The previous prime is 21241640429. The next prime is 21241640473. The reversal of 21241640456 is 65404614212.

It can be written as a sum of positive squares in only one way, i.e., 20639919556 + 601720900 = 143666^2 + 24530^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1327602521 + ... + 1327602536.

Almost surely, 2^21241640456 is an apocalyptic number.

It is an amenable number.

21241640456 is a deficient number, since it is larger than the sum of its proper divisors (18586435414).

21241640456 is a wasteful number, since it uses less digits than its factorization.

21241640456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2655205063 (or 2655205059 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 35.

The spelling of 21241640456 in words is "twenty-one billion, two hundred forty-one million, six hundred forty thousand, four hundred fifty-six".