64643571001 has 9 divisors (see below), whose sum is σ = 65585182159. Its totient is φ = 63715300600.

The previous prime is 64643570993. The next prime is 64643571011. The reversal of 64643571001 is 10017534646.

The square root of 64643571001 is 254251.

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

It can be written as a sum of positive squares in only one way, i.e., 57624482601 + 7019088400 = 240051^2 + 83780^2 .

It is not a de Polignac number, because 64643571001 - 2³ = 64643570993 is a prime.

It is a super-2 number, since 2×64643571001² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64643571011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 18050031 + ... + 18053611.

Almost surely, 2^64643571001 is an apocalyptic number.

64643571001 is the 254251-st square number.

64643571001 is the 127126-th centered octagonal number.

It is an amenable number.

64643571001 is a deficient number, since it is larger than the sum of its proper divisors (941611158).

64643571001 is an frugal number, since it uses more digits than its factorization.

64643571001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7304 (or 3652 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 37.

The spelling of 64643571001 in words is "sixty-four billion, six hundred forty-three million, five hundred seventy-one thousand, one".