649101985 has 16 divisors (see below), whose sum is σ = 910901376. Its totient is φ = 434746368.

The previous prime is 649101979. The next prime is 649101991. The reversal of 649101985 is 589101946.

It is an interprime number because it is at equal distance from previous prime (649101979) and next prime (649101991).

It is not a de Polignac number, because 649101985 - 2⁷ = 649101857 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 214144 + ... + 217153.

It is an arithmetic number, because the mean of its divisors is an integer number (56931336).

Almost surely, 2^649101985 is an apocalyptic number.

It is an amenable number.

649101985 is a deficient number, since it is larger than the sum of its proper divisors (261799391).

649101985 is a wasteful number, since it uses less digits than its factorization.

649101985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 431352.

The product of its (nonzero) digits is 77760, while the sum is 43.

The square root of 649101985 is about 25477.4799577980. The cubic root of 649101985 is about 865.8400006115.

It can be divided in two parts, 649 and 101985, that multiplied together give a triangular number (66188265 = T₁₁₅₀₅).

The spelling of 649101985 in words is "six hundred forty-nine million, one hundred one thousand, nine hundred eighty-five".