648442467947 has 4 divisors (see below), whose sum is σ = 648460774056. Its totient is φ = 648424161840.

The previous prime is 648442467943. The next prime is 648442467949. The reversal of 648442467947 is 749764244846.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 749764244846 = 2 ⋅374882122423.

It is a cyclic number.

It is not a de Polignac number, because 648442467947 - 2² = 648442467943 is a prime.

It is a super-2 number, since 2×648442467947² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (648442467943) 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, 9099818 + ... + 9170799.

It is an arithmetic number, because the mean of its divisors is an integer number (162115193514).

Almost surely, 2^648442467947 is an apocalyptic number.

648442467947 is a deficient number, since it is larger than the sum of its proper divisors (18306109).

648442467947 is a wasteful number, since it uses less digits than its factorization.

648442467947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18306108.

The product of its digits is 260112384, while the sum is 65.

The spelling of 648442467947 in words is "six hundred forty-eight billion, four hundred forty-two million, four hundred sixty-seven thousand, nine hundred forty-seven".