65424299821 has 4 divisors (see below), whose sum is σ = 65456169532. Its totient is φ = 65392430112.

The previous prime is 65424299761. The next prime is 65424299827. The reversal of 65424299821 is 12899242456.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 12213344196 + 53210955625 = 110514^2 + 230675^2 .

It is a cyclic number.

It is not a de Polignac number, because 65424299821 - 2¹⁵ = 65424267053 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65424299827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15931776 + ... + 15935881.

It is an arithmetic number, because the mean of its divisors is an integer number (16364042383).

Almost surely, 2^65424299821 is an apocalyptic number.

It is an amenable number.

65424299821 is a deficient number, since it is larger than the sum of its proper divisors (31869711).

65424299821 is a wasteful number, since it uses less digits than its factorization.

65424299821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31869710.

The product of its digits is 2488320, while the sum is 52.

The spelling of 65424299821 in words is "sixty-five billion, four hundred twenty-four million, two hundred ninety-nine thousand, eight hundred twenty-one".