21242889715 has 8 divisors (see below), whose sum is σ = 25494858288. Its totient is φ = 16992051360.

The previous prime is 21242889709. The next prime is 21242889749. The reversal of 21242889715 is 51798824212.

It is a happy number.

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

It is not a de Polignac number, because 21242889715 - 2⁵ = 21242889683 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 240637 + ... + 316846.

It is an arithmetic number, because the mean of its divisors is an integer number (3186857286).

Almost surely, 2^21242889715 is an apocalyptic number.

21242889715 is a deficient number, since it is larger than the sum of its proper divisors (4251968573).

21242889715 is an equidigital number, since it uses as much as digits as its factorization.

21242889715 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 565109.

The product of its digits is 645120, while the sum is 49.

The spelling of 21242889715 in words is "twenty-one billion, two hundred forty-two million, eight hundred eighty-nine thousand, seven hundred fifteen".