100131978 has 16 divisors (see below), whose sum is σ = 202102560. Its totient is φ = 33070896.

The previous prime is 100131961. The next prime is 100132013. The reversal of 100131978 is 879131001.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 75900 + ... + 77207.

It is an arithmetic number, because the mean of its divisors is an integer number (12631410).

Almost surely, 2^100131978 is an apocalyptic number.

100131978 is an abundant number, since it is smaller than the sum of its proper divisors (101970582).

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

100131978 is a wasteful number, since it uses less digits than its factorization.

100131978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153221.

The product of its (nonzero) digits is 1512, while the sum is 30.

The square root of 100131978 is about 10006.5967241615. The cubic root of 100131978 is about 464.3629894662.

Adding to 100131978 its reverse (879131001), we get a palindrome (979262979).

The spelling of 100131978 in words is "one hundred million, one hundred thirty-one thousand, nine hundred seventy-eight".