999961278 has 8 divisors (see below), whose sum is σ = 1999922568. Its totient is φ = 333320424.

The previous prime is 999961273. The next prime is 999961289. The reversal of 999961278 is 872169999.

It is a happy number.

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

999961278 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999961273) 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, 83330101 + ... + 83330112.

It is an arithmetic number, because the mean of its divisors is an integer number (249990321).

Almost surely, 2^999961278 is an apocalyptic number.

999961278 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

999961278 is a wasteful number, since it uses less digits than its factorization.

999961278 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166660218.

The product of its digits is 4408992, while the sum is 60.

The square root of 999961278 is about 31622.1643471790. The cubic root of 999961278 is about 999.9870925001.

The spelling of 999961278 in words is "nine hundred ninety-nine million, nine hundred sixty-one thousand, two hundred seventy-eight".