648391990 has 8 divisors (see below), whose sum is σ = 1167105600. Its totient is φ = 259356792.

The previous prime is 648391987. The next prime is 648392027. The reversal of 648391990 is 99193846.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32419590 + ... + 32419609.

It is an arithmetic number, because the mean of its divisors is an integer number (145888200).

Almost surely, 2^648391990 is an apocalyptic number.

648391990 is a deficient number, since it is larger than the sum of its proper divisors (518713610).

648391990 is a wasteful number, since it uses less digits than its factorization.

648391990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64839206.

The product of its (nonzero) digits is 419904, while the sum is 49.

The square root of 648391990 is about 25463.5423694348. The cubic root of 648391990 is about 865.5241969530.

The spelling of 648391990 in words is "six hundred forty-eight million, three hundred ninety-one thousand, nine hundred ninety".