649317481 has 4 divisors (see below), whose sum is σ = 649392964. Its totient is φ = 649242000.

The previous prime is 649317443. The next prime is 649317491. The reversal of 649317481 is 184713946.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 184713946 = 2 ⋅92356973.

It can be written as a sum of positive squares in 2 ways, for example, as 311346025 + 337971456 = 17645^2 + 18384^2 .

It is a cyclic number.

It is not a de Polignac number, because 649317481 - 2¹³ = 649309289 is a prime.

It is a super-2 number, since 2×649317481² = 843226382264370722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (649317401) 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, 22890 + ... + 42691.

It is an arithmetic number, because the mean of its divisors is an integer number (162348241).

Almost surely, 2^649317481 is an apocalyptic number.

It is an amenable number.

649317481 is a deficient number, since it is larger than the sum of its proper divisors (75483).

649317481 is an equidigital number, since it uses as much as digits as its factorization.

649317481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75482.

The product of its digits is 145152, while the sum is 43.

The square root of 649317481 is about 25481.7087535353. The cubic root of 649317481 is about 865.9358070316.

The spelling of 649317481 in words is "six hundred forty-nine million, three hundred seventeen thousand, four hundred eighty-one".