64550813 has 2 divisors, whose sum is σ = 64550814. Its totient is φ = 64550812.

The previous prime is 64550807. The next prime is 64550831. The reversal of 64550813 is 31805546.

It is a happy number.

Together with next prime (64550831) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 48972004 + 15578809 = 6998^2 + 3947^2 .

It is a cyclic number.

It is not a de Polignac number, because 64550813 - 2⁴ = 64550797 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 64550813.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64540813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32275406 + 32275407.

It is an arithmetic number, because the mean of its divisors is an integer number (32275407).

Almost surely, 2^64550813 is an apocalyptic number.

It is an amenable number.

64550813 is a deficient number, since it is larger than the sum of its proper divisors (1).

64550813 is an equidigital number, since it uses as much as digits as its factorization.

64550813 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14400, while the sum is 32.

The square root of 64550813 is about 8034.3520585048. The cubic root of 64550813 is about 401.1442506880.

The spelling of 64550813 in words is "sixty-four million, five hundred fifty thousand, eight hundred thirteen".