981428978 has 4 divisors (see below), whose sum is σ = 1472143470. Its totient is φ = 490714488.

The previous prime is 981428963. The next prime is 981428993. The reversal of 981428978 is 879824189.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 879824189 = 6397 ⋅137537.

It is an interprime number because it is at equal distance from previous prime (981428963) and next prime (981428993).

It can be written as a sum of positive squares in only one way, i.e., 762477769 + 218951209 = 27613^2 + 14797^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245357243 + ... + 245357246.

Almost surely, 2^981428978 is an apocalyptic number.

981428978 is a deficient number, since it is larger than the sum of its proper divisors (490714492).

981428978 is a wasteful number, since it uses less digits than its factorization.

981428978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 490714491.

The product of its digits is 2322432, while the sum is 56.

The square root of 981428978 is about 31327.7668849856. The cubic root of 981428978 is about 993.7709386936.

The spelling of 981428978 in words is "nine hundred eighty-one million, four hundred twenty-eight thousand, nine hundred seventy-eight".