649239263 has 4 divisors (see below), whose sum is σ = 649527168. Its totient is φ = 648951360.

The previous prime is 649239257. The next prime is 649239271. The reversal of 649239263 is 362932946.

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

It is a cyclic number.

It is not a de Polignac number, because 649239263 - 2⁸ = 649239007 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (649239203) 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, 140543 + ... + 145088.

It is an arithmetic number, because the mean of its divisors is an integer number (162381792).

Almost surely, 2^649239263 is an apocalyptic number.

649239263 is a deficient number, since it is larger than the sum of its proper divisors (287905).

649239263 is a wasteful number, since it uses less digits than its factorization.

649239263 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 287904.

The product of its digits is 419904, while the sum is 44.

The square root of 649239263 is about 25480.1739201286. The cubic root of 649239263 is about 865.9010348856.

The spelling of 649239263 in words is "six hundred forty-nine million, two hundred thirty-nine thousand, two hundred sixty-three".