1978425 has 30 divisors (see below), whose sum is σ = 3668478. Its totient is φ = 1054080.

The previous prime is 1978423. The next prime is 1978429. The reversal of 1978425 is 5248791.

It can be written as a sum of positive squares in 3 ways, for example, as 480249 + 1498176 = 693^2 + 1224^2 .

It is not a de Polignac number, because 1978425 - 2¹ = 1978423 is a prime.

1978425 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 1978425.

It is not an unprimeable number, because it can be changed into a prime (1978421) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 1537 + ... + 2513.

2^1978425 is an apocalyptic number.

1978425 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1978425 is a deficient number, since it is larger than the sum of its proper divisors (1690053).

1978425 is an equidigital number, since it uses as much as digits as its factorization.

1978425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 999 (or 985 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 1978425 is about 1406.5649647279. The cubic root of 1978425 is about 125.5374194646.

The spelling of 1978425 in words is "one million, nine hundred seventy-eight thousand, four hundred twenty-five".