1019720656 has 20 divisors (see below), whose sum is σ = 2091927492. Its totient is φ = 479868416.

The previous prime is 1019720651. The next prime is 1019720657. The reversal of 1019720656 is 6560279101.

It can be written as a sum of positive squares in 2 ways, for example, as 571975056 + 447745600 = 23916^2 + 21160^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1019720651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1874215 + ... + 1874758.

Almost surely, 2^1019720656 is an apocalyptic number.

1019720656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1019720656 is an abundant number, since it is smaller than the sum of its proper divisors (1072206836).

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

1019720656 is a wasteful number, since it uses less digits than its factorization.

1019720656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3748998 (or 3748992 counting only the distinct ones).

The product of its (nonzero) digits is 22680, while the sum is 37.

The square root of 1019720656 is about 31933.0652459171. The cubic root of 1019720656 is about 1006.5308077013.

Adding to 1019720656 its reverse (6560279101), we get a palindrome (7579999757).

The spelling of 1019720656 in words is "one billion, nineteen million, seven hundred twenty thousand, six hundred fifty-six".