649440601 has 4 divisors (see below), whose sum is σ = 649491892. Its totient is φ = 649389312.

The previous prime is 649440551. The next prime is 649440611. The reversal of 649440601 is 106044946.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 606341376 + 43099225 = 24624^2 + 6565^2 .

It is a cyclic number.

It is not a de Polignac number, because 649440601 - 2¹⁵ = 649407833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (649440611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8521 + ... + 37033.

It is an arithmetic number, because the mean of its divisors is an integer number (162372973).

Almost surely, 2^649440601 is an apocalyptic number.

It is an amenable number.

649440601 is a deficient number, since it is larger than the sum of its proper divisors (51291).

649440601 is a wasteful number, since it uses less digits than its factorization.

649440601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51290.

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 649440601 is about 25484.1244895719. The cubic root of 649440601 is about 865.9905348968.

The spelling of 649440601 in words is "six hundred forty-nine million, four hundred forty thousand, six hundred one".