1978506 has 56 divisors (see below), whose sum is σ = 4721760. Its totient is φ = 620136.

The previous prime is 1978469. The next prime is 1978507. The reversal of 1978506 is 6058791.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1978507) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 33505 + ... + 33563.

2^1978506 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1978506, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2360880).

1978506 is an abundant number, since it is smaller than the sum of its proper divisors (2743254).

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

1978506 is an equidigital number, since it uses as much as digits as its factorization.

1978506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102 (or 87 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 36.

The square root of 1978506 is about 1406.5937579842. The cubic root of 1978506 is about 125.5391326779.

The spelling of 1978506 in words is "one million, nine hundred seventy-eight thousand, five hundred six".