65197809 has 12 divisors (see below), whose sum is σ = 95501952. Its totient is φ = 42852600.

The previous prime is 65197807. The next prime is 65197813. The reversal of 65197809 is 90879156.

It is not a de Polignac number, because 65197809 - 2¹ = 65197807 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (65197807) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 50377 + ... + 51654.

It is an arithmetic number, because the mean of its divisors is an integer number (7958496).

Almost surely, 2^65197809 is an apocalyptic number.

It is an amenable number.

65197809 is a deficient number, since it is larger than the sum of its proper divisors (30304143).

65197809 is a wasteful number, since it uses less digits than its factorization.

65197809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102108 (or 102105 counting only the distinct ones).

The product of its (nonzero) digits is 136080, while the sum is 45.

The square root of 65197809 is about 8074.5160226480. The cubic root of 65197809 is about 402.4800273000.

The spelling of 65197809 in words is "sixty-five million, one hundred ninety-seven thousand, eight hundred nine".