65775537840 has 40 divisors (see below), whose sum is σ = 203904168048. Its totient is φ = 17540143360.

The previous prime is 65775537823. The next prime is 65775537869. The reversal of 65775537840 is 4873557756.

It is a tau number, because it is divible by the number of its divisors (40).

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, 137032131 + ... + 137032610.

Almost surely, 2^65775537840 is an apocalyptic number.

65775537840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

65775537840 is an abundant number, since it is smaller than the sum of its proper divisors (138128630208).

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

65775537840 is a wasteful number, since it uses less digits than its factorization.

65775537840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 274064757 (or 274064751 counting only the distinct ones).

The product of its (nonzero) digits is 24696000, while the sum is 57.

The spelling of 65775537840 in words is "sixty-five billion, seven hundred seventy-five million, five hundred thirty-seven thousand, eight hundred forty".