1990478 has 24 divisors (see below), whose sum is σ = 3659400. Its totient is φ = 807408.

The previous prime is 1990463. The next prime is 1990481. The reversal of 1990478 is 8740991.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1328 + ... + 2396.

It is an arithmetic number, because the mean of its divisors is an integer number (152475).

2^1990478 is an apocalyptic number.

1990478 is a deficient number, since it is larger than the sum of its proper divisors (1668922).

1990478 is a wasteful number, since it uses less digits than its factorization.

1990478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1104 (or 1097 counting only the distinct ones).

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

The square root of 1990478 is about 1410.8430104019. The cubic root of 1990478 is about 125.7918373571.

The spelling of 1990478 in words is "one million, nine hundred ninety thousand, four hundred seventy-eight".