978726997 has 8 divisors (see below), whose sum is σ = 1006623800. Its totient is φ = 950906304.

The previous prime is 978726979. The next prime is 978727019. The reversal of 978726997 is 799627879.

It can be written as a sum of positive squares in 4 ways, for example, as 154405476 + 824321521 = 12426^2 + 28711^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 978726997 - 2²³ = 970338389 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 (978726937) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7579 + ... + 44887.

It is an arithmetic number, because the mean of its divisors is an integer number (125827975).

Almost surely, 2^978726997 is an apocalyptic number.

It is an amenable number.

978726997 is a deficient number, since it is larger than the sum of its proper divisors (27896803).

978726997 is a wasteful number, since it uses less digits than its factorization.

978726997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38055.

The product of its digits is 24004512, while the sum is 64.

The square root of 978726997 is about 31284.6127832837. The cubic root of 978726997 is about 992.8581138904.

The spelling of 978726997 in words is "nine hundred seventy-eight million, seven hundred twenty-six thousand, nine hundred ninety-seven".