21542750065 has 8 divisors (see below), whose sum is σ = 26215403328. Its totient is φ = 16991464560.

The previous prime is 21542750059. The next prime is 21542750147. The reversal of 21542750065 is 56005724512.

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

It is not a de Polignac number, because 21542750065 - 2⁷ = 21542749937 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 (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30341547 + ... + 30342256.

It is an arithmetic number, because the mean of its divisors is an integer number (3276925416).

Almost surely, 2^21542750065 is an apocalyptic number.

It is an amenable number.

21542750065 is a deficient number, since it is larger than the sum of its proper divisors (4672653263).

21542750065 is an equidigital number, since it uses as much as digits as its factorization.

21542750065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60683879.

The product of its (nonzero) digits is 84000, while the sum is 37.

The spelling of 21542750065 in words is "twenty-one billion, five hundred forty-two million, seven hundred fifty thousand, sixty-five".