648437641 has 4 divisors (see below), whose sum is σ = 653102800. Its totient is φ = 643772484.

The previous prime is 648437627. The next prime is 648437659. The reversal of 648437641 is 146734846.

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 not a de Polignac number, because 648437641 - 2⁷ = 648437513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (648837641) 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, 2332371 + ... + 2332648.

It is an arithmetic number, because the mean of its divisors is an integer number (163275700).

Almost surely, 2^648437641 is an apocalyptic number.

It is an amenable number.

648437641 is a deficient number, since it is larger than the sum of its proper divisors (4665159).

648437641 is a wasteful number, since it uses less digits than its factorization.

648437641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4665158.

The product of its digits is 387072, while the sum is 43.

The square root of 648437641 is about 25464.4387528962. The cubic root of 648437641 is about 865.5445093147.

The spelling of 648437641 in words is "six hundred forty-eight million, four hundred thirty-seven thousand, six hundred forty-one".