9999979 has 4 divisors (see below), whose sum is σ = 10909080.
Its totient is φ = 9090880.
The previous prime is 9999973. The next prime is 9999991. The reversal of 9999979 is 9799999.
9999979 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.
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 9999979 - 23 = 9999971 is a prime.
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (9999971) 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, 454534 + ... + 454555.
It is an arithmetic number, because the mean of its divisors is an integer number (2727270).
Almost surely, 29999979 is an apocalyptic number.
9999979 is a deficient number, since it is larger than the sum of its proper divisors (909101).
9999979 is a wasteful number, since it uses less digits than its factorization.
9999979 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 909100.
The product of its digits is 3720087, while the sum is 61.
The square root of 9999979 is about 3162.2743397751.
The cubic root of 9999979 is about 215.4433181927.
The spelling of 9999979 in words is "nine million, nine hundred ninety-nine thousand, nine hundred seventy-nine".