978041917 has 2 divisors, whose sum is σ = 978041918. Its totient is φ = 978041916.

The previous prime is 978041863. The next prime is 978041963. The reversal of 978041917 is 719140879.

It is an a-pointer prime, because the next prime (978041963) can be obtained adding 978041917 to its sum of digits (46).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 540981081 + 437060836 = 23259^2 + 20906^2 .

It is an emirp because it is prime and its reverse (719140879) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 978041917 - 2⁷ = 978041789 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (978041417) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 489020958 + 489020959.

It is an arithmetic number, because the mean of its divisors is an integer number (489020959).

Almost surely, 2^978041917 is an apocalyptic number.

It is an amenable number.

978041917 is a deficient number, since it is larger than the sum of its proper divisors (1).

978041917 is an equidigital number, since it uses as much as digits as its factorization.

978041917 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 127008, while the sum is 46.

The square root of 978041917 is about 31273.6617139727. The cubic root of 978041917 is about 992.6264026968.

The spelling of 978041917 in words is "nine hundred seventy-eight million, forty-one thousand, nine hundred seventeen".