8421542065 has 16 divisors (see below), whose sum is σ = 10632137040. Its totient is φ = 6395258880.

The previous prime is 8421542053. The next prime is 8421542191. The reversal of 8421542065 is 5602451248.

It can be written as a sum of positive squares in 8 ways, for example, as 1613146896 + 6808395169 = 40164^2 + 82513^2 .

It is not a de Polignac number, because 8421542065 - 2⁹ = 8421541553 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

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 15 ways as a sum of consecutive naturals, for example, 547560 + ... + 562729.

It is an arithmetic number, because the mean of its divisors is an integer number (664508565).

Almost surely, 2^8421542065 is an apocalyptic number.

It is an amenable number.

8421542065 is a deficient number, since it is larger than the sum of its proper divisors (2210594975).

8421542065 is a wasteful number, since it uses less digits than its factorization.

8421542065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1110372.

The product of its (nonzero) digits is 76800, while the sum is 37.

The square root of 8421542065 is about 91768.9602480054. The cubic root of 8421542065 is about 2034.5289506109.

The spelling of 8421542065 in words is "eight billion, four hundred twenty-one million, five hundred forty-two thousand, sixty-five".