648124421861 has 16 divisors (see below), whose sum is σ = 745663801344. Its totient is φ = 551826301104.

The previous prime is 648124421831. The next prime is 648124421869. The reversal of 648124421861 is 168124421846.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-648124421861 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (648124421869) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1953656 + ... + 2261198.

It is an arithmetic number, because the mean of its divisors is an integer number (46603987584).

Almost surely, 2^648124421861 is an apocalyptic number.

It is an amenable number.

648124421861 is a deficient number, since it is larger than the sum of its proper divisors (97539379483).

648124421861 is a wasteful number, since it uses less digits than its factorization.

648124421861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 309560.

The product of its digits is 589824, while the sum is 47.

The spelling of 648124421861 in words is "six hundred forty-eight billion, one hundred twenty-four million, four hundred twenty-one thousand, eight hundred sixty-one".