1389757661 has 2 divisors, whose sum is σ = 1389757662. Its totient is φ = 1389757660.

The previous prime is 1389757637. The next prime is 1389757741. The reversal of 1389757661 is 1667579831.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1383096100 + 6661561 = 37190^2 + 2581^2 .

It is a cyclic number.

It is not a de Polignac number, because 1389757661 - 2¹⁰ = 1389756637 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1389757861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 694878830 + 694878831.

It is an arithmetic number, because the mean of its divisors is an integer number (694878831).

Almost surely, 2^1389757661 is an apocalyptic number.

It is an amenable number.

1389757661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1389757661 is an equidigital number, since it uses as much as digits as its factorization.

1389757661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1905120, while the sum is 53.

The square root of 1389757661 is about 37279.4536038285. The cubic root of 1389757661 is about 1115.9541688527.

The spelling of 1389757661 in words is "one billion, three hundred eighty-nine million, seven hundred fifty-seven thousand, six hundred sixty-one".