64731709 has 16 divisors (see below), whose sum is σ = 75945600. Its totient is φ = 54025920.

The previous prime is 64731707. The next prime is 64731739. The reversal of 64731709 is 90713746.

It is a cyclic number.

It is not a de Polignac number, because 64731709 - 2¹ = 64731707 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64731707) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 54694 + ... + 55864.

It is an arithmetic number, because the mean of its divisors is an integer number (4746600).

Almost surely, 2^64731709 is an apocalyptic number.

It is an amenable number.

64731709 is a deficient number, since it is larger than the sum of its proper divisors (11213891).

64731709 is a wasteful number, since it uses less digits than its factorization.

64731709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1380.

The product of its (nonzero) digits is 31752, while the sum is 37.

The square root of 64731709 is about 8045.6018420004. The cubic root of 64731709 is about 401.5186209298.

The spelling of 64731709 in words is "sixty-four million, seven hundred thirty-one thousand, seven hundred nine".