649505757601 has 4 divisors (see below), whose sum is σ = 651005771332. Its totient is φ = 648005743872.

The previous prime is 649505757581. The next prime is 649505757613. The reversal of 649505757601 is 106757505946.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 293765084001 + 355740673600 = 542001^2 + 596440^2 .

It is a cyclic number.

It is not a de Polignac number, because 649505757601 - 2¹¹ = 649505755553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (649505757101) 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, 750006216 + ... + 750007081.

It is an arithmetic number, because the mean of its divisors is an integer number (162751442833).

Almost surely, 2^649505757601 is an apocalyptic number.

It is an amenable number.

649505757601 is a deficient number, since it is larger than the sum of its proper divisors (1500013731).

649505757601 is a wasteful number, since it uses less digits than its factorization.

649505757601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1500013730.

The product of its (nonzero) digits is 7938000, while the sum is 55.

The spelling of 649505757601 in words is "six hundred forty-nine billion, five hundred five million, seven hundred fifty-seven thousand, six hundred one".