1945816709 has 6 divisors (see below), whose sum is σ = 1958314194. Its totient is φ = 1933398480.

The previous prime is 1945816703. The next prime is 1945816723. The reversal of 1945816709 is 9076185491.

It can be written as a sum of positive squares in 3 ways, for example, as 124609 + 1945692100 = 353^2 + 44110^2 .

It is not a de Polignac number, because 1945816709 - 2¹⁶ = 1945751173 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1945816703) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 14822 + ... + 64119.

It is an arithmetic number, because the mean of its divisors is an integer number (326385699).

Almost surely, 2^1945816709 is an apocalyptic number.

It is an amenable number.

1945816709 is a deficient number, since it is larger than the sum of its proper divisors (12497485).

1945816709 is an frugal number, since it uses more digits than its factorization.

1945816709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79255 (or 79098 counting only the distinct ones).

The product of its (nonzero) digits is 544320, while the sum is 50.

The square root of 1945816709 is about 44111.4124575489. The cubic root of 1945816709 is about 1248.4389492279.

The spelling of 1945816709 in words is "one billion, nine hundred forty-five million, eight hundred sixteen thousand, seven hundred nine".