642206565 has 192 divisors, whose sum is σ = 1528450560. Its totient is φ = 240814080.

The previous prime is 642206561. The next prime is 642206599. The reversal of 642206565 is 565602246.

642206565 is a `hidden beast` number, since 642 + 2 + 0 + 6 + 5 + 6 + 5 = 666.

642206565 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 642206565 - 2² = 642206561 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642206561) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 2387251 + ... + 2387519.

It is an arithmetic number, because the mean of its divisors is an integer number (7960680).

Almost surely, 2^642206565 is an apocalyptic number.

642206565 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

642206565 is an abundant number, since it is smaller than the sum of its proper divisors (886243995).

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

642206565 is a wasteful number, since it uses less digits than its factorization.

642206565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 364 (or 361 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 36.

The square root of 642206565 is about 25341.7948259392. The cubic root of 642206565 is about 862.7631358441.

The spelling of 642206565 in words is "six hundred forty-two million, two hundred six thousand, five hundred sixty-five".