1009779961 has 4 divisors (see below), whose sum is σ = 1010959092. Its totient is φ = 1008600832.

The previous prime is 1009779943. The next prime is 1009779973. The reversal of 1009779961 is 1699779001.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 624050361 + 385729600 = 24981^2 + 19640^2 .

It is a cyclic number.

It is not a de Polignac number, because 1009779961 - 2¹³ = 1009771769 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1009779931) by changing a digit.

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, 588280 + ... + 589993.

It is an arithmetic number, because the mean of its divisors is an integer number (252739773).

Almost surely, 2^1009779961 is an apocalyptic number.

It is an amenable number.

1009779961 is a deficient number, since it is larger than the sum of its proper divisors (1179131).

1009779961 is an equidigital number, since it uses as much as digits as its factorization.

1009779961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1179130.

The product of its (nonzero) digits is 214326, while the sum is 49.

The square root of 1009779961 is about 31777.0351197213. The cubic root of 1009779961 is about 1003.2494168536.

The spelling of 1009779961 in words is "one billion, nine million, seven hundred seventy-nine thousand, nine hundred sixty-one".