64505273 has 4 divisors (see below), whose sum is σ = 73720320. Its totient is φ = 55290228.

The previous prime is 64505269. The next prime is 64505279. The reversal of 64505273 is 37250546.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 37250546 = 2 ⋅18625273.

It is not a de Polignac number, because 64505273 - 2² = 64505269 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64505279) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4607513 + ... + 4607526.

It is an arithmetic number, because the mean of its divisors is an integer number (18430080).

Almost surely, 2^64505273 is an apocalyptic number.

It is an amenable number.

64505273 is a deficient number, since it is larger than the sum of its proper divisors (9215047).

64505273 is an equidigital number, since it uses as much as digits as its factorization.

64505273 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9215046.

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

The square root of 64505273 is about 8031.5174780361. The cubic root of 64505273 is about 401.0498939789.

The spelling of 64505273 in words is "sixty-four million, five hundred five thousand, two hundred seventy-three".