648139820 has 12 divisors (see below), whose sum is σ = 1361093664. Its totient is φ = 259255920.

The previous prime is 648139781. The next prime is 648139873. The reversal of 648139820 is 28931846.

It is a hoax number, since the sum of its digits (41) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16203476 + ... + 16203515.

It is an arithmetic number, because the mean of its divisors is an integer number (113424472).

Almost surely, 2^648139820 is an apocalyptic number.

It is an amenable number.

648139820 is an abundant number, since it is smaller than the sum of its proper divisors (712953844).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

648139820 is a wasteful number, since it uses less digits than its factorization.

648139820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32407000 (or 32406998 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 41.

The square root of 648139820 is about 25458.5902987577. The cubic root of 648139820 is about 865.4119770094.

The spelling of 648139820 in words is "six hundred forty-eight million, one hundred thirty-nine thousand, eight hundred twenty".