1989770 has 8 divisors (see below), whose sum is σ = 3581604. Its totient is φ = 795904.

The previous prime is 1989769. The next prime is 1989787. The reversal of 1989770 is 779891.

It can be written as a sum of positive squares in 2 ways, for example, as 1985281 + 4489 = 1409^2 + 67^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an Ulam number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 99479 + ... + 99498.

2^1989770 is an apocalyptic number.

1989770 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1989770 is a deficient number, since it is larger than the sum of its proper divisors (1591834).

1989770 is a wasteful number, since it uses less digits than its factorization.

1989770 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198984.

The product of its (nonzero) digits is 31752, while the sum is 41.

The square root of 1989770 is about 1410.5920742724. The cubic root of 1989770 is about 125.7769211439.

The spelling of 1989770 in words is "one million, nine hundred eighty-nine thousand, seven hundred seventy".