1978481 has 4 divisors (see below), whose sum is σ = 1984500. Its totient is φ = 1972464.

The previous prime is 1978469. The next prime is 1978507. The reversal of 1978481 is 1848791.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1848791 = 7 ⋅264113.

It can be written as a sum of positive squares in 2 ways, for example, as 960400 + 1018081 = 980^2 + 1009^2 .

It is a cyclic number.

It is not a de Polignac number, because 1978481 - 2¹⁴ = 1962097 is a prime.

It is a super-2 number, since 2×1978481² = 7828774134722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1978411) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2486 + ... + 3183.

It is an arithmetic number, because the mean of its divisors is an integer number (496125).

2^1978481 is an apocalyptic number.

It is an amenable number.

1978481 is a deficient number, since it is larger than the sum of its proper divisors (6019).

1978481 is an equidigital number, since it uses as much as digits as its factorization.

1978481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6018.

The product of its digits is 16128, while the sum is 38.

The square root of 1978481 is about 1406.5848712396. The cubic root of 1978481 is about 125.5386039134.

The spelling of 1978481 in words is "one million, nine hundred seventy-eight thousand, four hundred eighty-one".