649566254257 has 4 divisors (see below), whose sum is σ = 649569734656. Its totient is φ = 649562773860.

The previous prime is 649566254221. The next prime is 649566254261. The reversal of 649566254257 is 752452665946.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-649566254257 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 649566254195 and 649566254204.

It is not an unprimeable number, because it can be changed into a prime (649566254287) 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, 1443369 + ... + 1839142.

It is an arithmetic number, because the mean of its divisors is an integer number (162392433664).

Almost surely, 2^649566254257 is an apocalyptic number.

It is an amenable number.

649566254257 is a deficient number, since it is larger than the sum of its proper divisors (3480399).

649566254257 is a wasteful number, since it uses less digits than its factorization.

649566254257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3480398.

The product of its digits is 108864000, while the sum is 61.

The spelling of 649566254257 in words is "six hundred forty-nine billion, five hundred sixty-six million, two hundred fifty-four thousand, two hundred fifty-seven".