1298890639 has 2 divisors, whose sum is σ = 1298890640. Its totient is φ = 1298890638.

The previous prime is 1298890633. The next prime is 1298890651. The reversal of 1298890639 is 9360988921.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1298890639 - 2³ = 1298890631 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1298890639.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1298890631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 649445319 + 649445320.

It is an arithmetic number, because the mean of its divisors is an integer number (649445320).

Almost surely, 2^1298890639 is an apocalyptic number.

1298890639 is a deficient number, since it is larger than the sum of its proper divisors (1).

1298890639 is an equidigital number, since it uses as much as digits as its factorization.

1298890639 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1679616, while the sum is 55.

The square root of 1298890639 is about 36040.1254021126. The cubic root of 1298890639 is about 1091.0823463270.

The spelling of 1298890639 in words is "one billion, two hundred ninety-eight million, eight hundred ninety thousand, six hundred thirty-nine".