1012778309 has 2 divisors, whose sum is σ = 1012778310. Its totient is φ = 1012778308.

The previous prime is 1012778287. The next prime is 1012778317. The reversal of 1012778309 is 9038772101.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 948024100 + 64754209 = 30790^2 + 8047^2 .

It is an emirp because it is prime and its reverse (9038772101) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1012778309 - 2¹⁶ = 1012712773 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1012778329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 506389154 + 506389155.

It is an arithmetic number, because the mean of its divisors is an integer number (506389155).

Almost surely, 2^1012778309 is an apocalyptic number.

It is an amenable number.

1012778309 is a deficient number, since it is larger than the sum of its proper divisors (1).

1012778309 is an equidigital number, since it uses as much as digits as its factorization.

1012778309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21168, while the sum is 38.

The square root of 1012778309 is about 31824.1780569428. The cubic root of 1012778309 is about 1004.2414212453.

The spelling of 1012778309 in words is "one billion, twelve million, seven hundred seventy-eight thousand, three hundred nine".