1649317780 has 24 divisors (see below), whose sum is σ = 3778437600. Its totient is φ = 599751840.

The previous prime is 1649317777. The next prime is 1649317837. The reversal of 1649317780 is 877139461.

It is a self number, because there is not a number n which added to its sum of digits gives 1649317780.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3748230 + ... + 3748669.

It is an arithmetic number, because the mean of its divisors is an integer number (157434900).

Almost surely, 2^1649317780 is an apocalyptic number.

1649317780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1649317780 is an abundant number, since it is smaller than the sum of its proper divisors (2129119820).

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

1649317780 is a wasteful number, since it uses less digits than its factorization.

1649317780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7496919 (or 7496917 counting only the distinct ones).

The product of its (nonzero) digits is 254016, while the sum is 46.

The square root of 1649317780 is about 40611.7936072762. The cubic root of 1649317780 is about 1181.5028682170.

The spelling of 1649317780 in words is "one billion, six hundred forty-nine million, three hundred seventeen thousand, seven hundred eighty".