1389089857 has 2 divisors, whose sum is σ = 1389089858. Its totient is φ = 1389089856.

The previous prime is 1389089837. The next prime is 1389089869. The reversal of 1389089857 is 7589809831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1039998001 + 349091856 = 32249^2 + 18684^2 .

It is a cyclic number.

It is not a de Polignac number, because 1389089857 - 2¹⁹ = 1388565569 is a prime.

It is not a weakly prime, because it can be changed into another prime (1389089837) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 694544928 + 694544929.

It is an arithmetic number, because the mean of its divisors is an integer number (694544929).

Almost surely, 2^1389089857 is an apocalyptic number.

It is an amenable number.

1389089857 is a deficient number, since it is larger than the sum of its proper divisors (1).

1389089857 is an equidigital number, since it uses as much as digits as its factorization.

1389089857 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4354560, while the sum is 58.

The square root of 1389089857 is about 37270.4957976145. The cubic root of 1389089857 is about 1115.7753947451.

The spelling of 1389089857 in words is "one billion, three hundred eighty-nine million, eighty-nine thousand, eight hundred fifty-seven".