100019978 has 16 divisors (see below), whose sum is σ = 153985920. Its totient is φ = 48698496.

The previous prime is 100019977. The next prime is 100020023. The reversal of 100019978 is 879910001.

It is not an unprimeable number, because it can be changed into a prime (100019977) 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, 29978 + ... + 33146.

It is an arithmetic number, because the mean of its divisors is an integer number (9624120).

Almost surely, 2^100019978 is an apocalyptic number.

100019978 is a deficient number, since it is larger than the sum of its proper divisors (53965942).

100019978 is a wasteful number, since it uses less digits than its factorization.

100019978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3581.

The product of its (nonzero) digits is 4536, while the sum is 35.

The square root of 100019978 is about 10000.9988501149. The cubic root of 100019978 is about 464.1897911904.

Adding to 100019978 its reverse (879910001), we get a palindrome (979929979).

The spelling of 100019978 in words is "one hundred million, nineteen thousand, nine hundred seventy-eight".