978404879 has 4 divisors (see below), whose sum is σ = 979521384. Its totient is φ = 977288376.

The previous prime is 978404851. The next prime is 978404881.

978404879 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 978404879 - 2¹² = 978400783 is a prime.

It is a super-2 number, since 2×978404879² = 1914552214502009282, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (978404849) 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, 556937 + ... + 558690.

It is an arithmetic number, because the mean of its divisors is an integer number (244880346).

Almost surely, 2^978404879 is an apocalyptic number.

978404879 is a deficient number, since it is larger than the sum of its proper divisors (1116505).

978404879 is a wasteful number, since it uses less digits than its factorization.

978404879 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1116504.

The product of its (nonzero) digits is 4064256, while the sum is 56.

The square root of 978404879 is about 31279.4641737994. The cubic root of 978404879 is about 992.7491789973.

The spelling of 978404879 in words is "nine hundred seventy-eight million, four hundred four thousand, eight hundred seventy-nine".