649740905 has 32 divisors (see below), whose sum is σ = 880225920. Its totient is φ = 456261120.

The previous prime is 649740893. The next prime is 649740907. The reversal of 649740905 is 509047946.

It is not a de Polignac number, because 649740905 - 2⁶ = 649740841 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (649740907) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 281717 + ... + 284013.

It is an arithmetic number, because the mean of its divisors is an integer number (27507060).

Almost surely, 2^649740905 is an apocalyptic number.

It is an amenable number.

649740905 is a deficient number, since it is larger than the sum of its proper divisors (230485015).

649740905 is a wasteful number, since it uses less digits than its factorization.

649740905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2489.

The product of its (nonzero) digits is 272160, while the sum is 44.

The square root of 649740905 is about 25490.0157905012. The cubic root of 649740905 is about 866.1239935211.

The spelling of 649740905 in words is "six hundred forty-nine million, seven hundred forty thousand, nine hundred five".