65539978829 has 16 divisors (see below), whose sum is σ = 72347625840. Its totient is φ = 58986455040.

The previous prime is 65539978799. The next prime is 65539978871. The reversal of 65539978829 is 92887993556.

It can be written as a sum of positive squares in 8 ways, for example, as 3484186729 + 62055792100 = 59027^2 + 249110^2 .

It is a cyclic number.

It is not a de Polignac number, because 65539978829 - 2⁸ = 65539978573 is a prime.

It is a super-2 number, since 2×65539978829² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65539978129) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 846077 + ... + 920285.

It is an arithmetic number, because the mean of its divisors is an integer number (4521726615).

Almost surely, 2^65539978829 is an apocalyptic number.

It is an amenable number.

65539978829 is a deficient number, since it is larger than the sum of its proper divisors (6807647011).

65539978829 is a wasteful number, since it uses less digits than its factorization.

65539978829 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75920.

The product of its digits is 293932800, while the sum is 71.

The spelling of 65539978829 in words is "sixty-five billion, five hundred thirty-nine million, nine hundred seventy-eight thousand, eight hundred twenty-nine".