1331990 has 16 divisors (see below), whose sum is σ = 2615760. Its totient is φ = 484320.

The previous prime is 1331989. The next prime is 1332017. The reversal of 1331990 is 991331.

1331990 = T₁₈₀ + T₁₈₁ + ... + T₂₃₉.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5945 + ... + 6164.

It is an arithmetic number, because the mean of its divisors is an integer number (163485).

2^1331990 is an apocalyptic number.

1331990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1331990 is a deficient number, since it is larger than the sum of its proper divisors (1283770).

1331990 is a wasteful number, since it uses less digits than its factorization.

1331990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12127.

The product of its (nonzero) digits is 729, while the sum is 26.

The square root of 1331990 is about 1154.1187113984. The cubic root of 1331990 is about 110.0272659682.

The spelling of 1331990 in words is "one million, three hundred thirty-one thousand, nine hundred ninety".