64720553 has 2 divisors, whose sum is σ = 64720554. Its totient is φ = 64720552.

The previous prime is 64720543. The next prime is 64720561. The reversal of 64720553 is 35502746.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 47844889 + 16875664 = 6917^2 + 4108^2 .

It is a cyclic number.

It is not a de Polignac number, because 64720553 - 2⁸ = 64720297 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (64720543) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32360276 + 32360277.

It is an arithmetic number, because the mean of its divisors is an integer number (32360277).

Almost surely, 2^64720553 is an apocalyptic number.

It is an amenable number.

64720553 is a deficient number, since it is larger than the sum of its proper divisors (1).

64720553 is an equidigital number, since it uses as much as digits as its factorization.

64720553 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25200, while the sum is 32.

The square root of 64720553 is about 8044.9085140852. The cubic root of 64720553 is about 401.4955534144.

The spelling of 64720553 in words is "sixty-four million, seven hundred twenty thousand, five hundred fifty-three".