678970987 has 4 divisors (see below), whose sum is σ = 681788536. Its totient is φ = 676153440.

The previous prime is 678970967. The next prime is 678970991. The reversal of 678970987 is 789079876.

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 678970987 - 2²³ = 670582379 is a prime.

It is a super-2 number, since 2×678970987² = 922003202375508338, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (678970907) 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, 1408413 + ... + 1408894.

It is an arithmetic number, because the mean of its divisors is an integer number (170447134).

Almost surely, 2^678970987 is an apocalyptic number.

678970987 is a deficient number, since it is larger than the sum of its proper divisors (2817549).

678970987 is a wasteful number, since it uses less digits than its factorization.

678970987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2817548.

The product of its (nonzero) digits is 10668672, while the sum is 61.

The square root of 678970987 is about 26057.0717272682. The cubic root of 678970987 is about 878.9221423729.

The spelling of 678970987 in words is "six hundred seventy-eight million, nine hundred seventy thousand, nine hundred eighty-seven".