1978490 has 16 divisors (see below), whose sum is σ = 3629448. Its totient is φ = 776256.

The previous prime is 1978469. The next prime is 1978507. The reversal of 1978490 is 948791.

It can be written as a sum of positive squares in 4 ways, for example, as 1776889 + 201601 = 1333^2 + 449^2 .

It is a congruent 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 7 ways as a sum of consecutive naturals, for example, 1337 + ... + 2396.

2^1978490 is an apocalyptic number.

1978490 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1978490 is a deficient number, since it is larger than the sum of its proper divisors (1650958).

1978490 is a wasteful number, since it uses less digits than its factorization.

1978490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3793.

The product of its (nonzero) digits is 18144, while the sum is 38.

The square root of 1978490 is about 1406.5880704741. The cubic root of 1978490 is about 125.5387942691.

The spelling of 1978490 in words is "one million, nine hundred seventy-eight thousand, four hundred ninety".