648623581477 has 4 divisors (see below), whose sum is σ = 648625265676. Its totient is φ = 648621897280.

The previous prime is 648623581453. The next prime is 648623581531. The reversal of 648623581477 is 774185326846.

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 206812114756 + 441811466721 = 454766^2 + 664689^2 .

It is a cyclic number.

It is not a de Polignac number, because 648623581477 - 2⁷ = 648623581349 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 (648683581477) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 52077 + ... + 1140157.

It is an arithmetic number, because the mean of its divisors is an integer number (162156316419).

Almost surely, 2^648623581477 is an apocalyptic number.

It is an amenable number.

648623581477 is a deficient number, since it is larger than the sum of its proper divisors (1684199).

648623581477 is a wasteful number, since it uses less digits than its factorization.

648623581477 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1684198.

The product of its digits is 54190080, while the sum is 61.

The spelling of 648623581477 in words is "six hundred forty-eight billion, six hundred twenty-three million, five hundred eighty-one thousand, four hundred seventy-seven".