978961805 has 4 divisors (see below), whose sum is σ = 1174754172. Its totient is φ = 783169440.

The previous prime is 978961801. The next prime is 978961817. The reversal of 978961805 is 508169879.

978961805 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 508169879 = 7 ⋅72595697.

It can be written as a sum of positive squares in 2 ways, for example, as 714118729 + 264843076 = 26723^2 + 16274^2 .

It is not a de Polignac number, because 978961805 - 2² = 978961801 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (978961801) 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, 97896176 + ... + 97896185.

It is an arithmetic number, because the mean of its divisors is an integer number (293688543).

Almost surely, 2^978961805 is an apocalyptic number.

It is an amenable number.

978961805 is a deficient number, since it is larger than the sum of its proper divisors (195792367).

978961805 is a wasteful number, since it uses less digits than its factorization.

978961805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195792366.

The product of its (nonzero) digits is 1088640, while the sum is 53.

The square root of 978961805 is about 31288.3653296237. The cubic root of 978961805 is about 992.9375069481.

The spelling of 978961805 in words is "nine hundred seventy-eight million, nine hundred sixty-one thousand, eight hundred five".