648351921 has 8 divisors (see below), whose sum is σ = 987964864. Its totient is φ = 370486800.

The previous prime is 648351919. The next prime is 648351931. The reversal of 648351921 is 129153846.

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

It is not a de Polignac number, because 648351921 - 2¹ = 648351919 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 648351921.

It is not an unprimeable number, because it can be changed into a prime (648351911) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15436930 + ... + 15436971.

It is an arithmetic number, because the mean of its divisors is an integer number (123495608).

Almost surely, 2^648351921 is an apocalyptic number.

It is an amenable number.

648351921 is a deficient number, since it is larger than the sum of its proper divisors (339612943).

648351921 is a wasteful number, since it uses less digits than its factorization.

648351921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30873911.

The product of its digits is 51840, while the sum is 39.

The square root of 648351921 is about 25462.7555657278. The cubic root of 648351921 is about 865.5063675103.

The spelling of 648351921 in words is "six hundred forty-eight million, three hundred fifty-one thousand, nine hundred twenty-one".