642608265 has 32 divisors (see below), whose sum is σ = 1109840256. Its totient is φ = 315624960.

The previous prime is 642608251. The next prime is 642608273. The reversal of 642608265 is 562806246.

It is not a de Polignac number, because 642608265 - 2⁴ = 642608249 is a prime.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 85510 + ... + 92720.

It is an arithmetic number, because the mean of its divisors is an integer number (34682508).

Almost surely, 2^642608265 is an apocalyptic number.

642608265 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

642608265 is a deficient number, since it is larger than the sum of its proper divisors (467231991).

642608265 is a wasteful number, since it uses less digits than its factorization.

642608265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7689.

The product of its (nonzero) digits is 138240, while the sum is 39.

The square root of 642608265 is about 25349.7192292144. The cubic root of 642608265 is about 862.9429843723.

The spelling of 642608265 in words is "six hundred forty-two million, six hundred eight thousand, two hundred sixty-five".