68645572009 has 15 divisors (see below), whose sum is σ = 80096715357. Its totient is φ = 58828057596.

The previous prime is 68645571949. The next prime is 68645572043. The reversal of 68645572009 is 90027554686.

The square root of 68645572009 is 262003.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 68645572009 - 2¹⁷ = 68645440937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68615572009) by changing a digit.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 12835474 + ... + 12840820.

Almost surely, 2^68645572009 is an apocalyptic number.

68645572009 is the 262003-rd square number.

68645572009 is the 131002-nd centered octagonal number.

It is an amenable number.

68645572009 is a deficient number, since it is larger than the sum of its proper divisors (11451143348).

68645572009 is an frugal number, since it uses more digits than its factorization.

68645572009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10722 (or 5354 counting only the distinct ones).

The product of its (nonzero) digits is 3628800, while the sum is 52.

The spelling of 68645572009 in words is "sixty-eight billion, six hundred forty-five million, five hundred seventy-two thousand, nine".