65645723868 has 24 divisors (see below), whose sum is σ = 153538936320. Its totient is φ = 21829682160.

The previous prime is 65645723849. The next prime is 65645723887. The reversal of 65645723868 is 86832754656.

It is an interprime number because it is at equal distance from previous prime (65645723849) and next prime (65645723887).

It is a super-2 number, since 2×65645723868² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6522988 + ... + 6533043.

It is an arithmetic number, because the mean of its divisors is an integer number (6397455680).

Almost surely, 2^65645723868 is an apocalyptic number.

It is an amenable number.

65645723868 is an abundant number, since it is smaller than the sum of its proper divisors (87893212452).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

65645723868 is a wasteful number, since it uses less digits than its factorization.

65645723868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13056457 (or 13056455 counting only the distinct ones).

The product of its digits is 58060800, while the sum is 60.

The spelling of 65645723868 in words is "sixty-five billion, six hundred forty-five million, seven hundred twenty-three thousand, eight hundred sixty-eight".