1289986890 has 64 divisors (see below), whose sum is σ = 3130348032. Its totient is φ = 340200000.

The previous prime is 1289986871. The next prime is 1289986921. The reversal of 1289986890 is 986899821.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1226865 + ... + 1227915.

It is an arithmetic number, because the mean of its divisors is an integer number (48911688).

Almost surely, 2^1289986890 is an apocalyptic number.

1289986890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1289986890 is an abundant number, since it is smaller than the sum of its proper divisors (1840361142).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1289986890 is a wasteful number, since it uses less digits than its factorization.

1289986890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1475.

The product of its (nonzero) digits is 4478976, while the sum is 60.

The square root of 1289986890 is about 35916.3874853805. The cubic root of 1289986890 is about 1088.5835457457.

The spelling of 1289986890 in words is "one billion, two hundred eighty-nine million, nine hundred eighty-six thousand, eight hundred ninety".