64645729 has 2 divisors, whose sum is σ = 64645730. Its totient is φ = 64645728.

The previous prime is 64645717. The next prime is 64645751. The reversal of 64645729 is 92754646.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 61230625 + 3415104 = 7825^2 + 1848^2 .

It is a cyclic number.

It is not a de Polignac number, because 64645729 - 2¹⁷ = 64514657 is a prime.

It is not a weakly prime, because it can be changed into another prime (64645129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32322864 + 32322865.

It is an arithmetic number, because the mean of its divisors is an integer number (32322865).

Almost surely, 2^64645729 is an apocalyptic number.

It is an amenable number.

64645729 is a deficient number, since it is larger than the sum of its proper divisors (1).

64645729 is an equidigital number, since it uses as much as digits as its factorization.

64645729 is an evil number, because the sum of its binary digits is even.

The product of its digits is 362880, while the sum is 43.

The square root of 64645729 is about 8040.2567745066. The cubic root of 64645729 is about 401.3407695710.

The spelling of 64645729 in words is "sixty-four million, six hundred forty-five thousand, seven hundred twenty-nine".