398978107 has 4 divisors (see below), whose sum is σ = 435248856. Its totient is φ = 362707360.

The previous prime is 398978081. The next prime is 398978137. The reversal of 398978107 is 701879893.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-398978107 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (398978137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18135358 + ... + 18135379.

It is an arithmetic number, because the mean of its divisors is an integer number (108812214).

Almost surely, 2^398978107 is an apocalyptic number.

398978107 is a deficient number, since it is larger than the sum of its proper divisors (36270749).

398978107 is a wasteful number, since it uses less digits than its factorization.

398978107 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36270748.

The product of its (nonzero) digits is 762048, while the sum is 52.

The square root of 398978107 is about 19974.4363374790. The cubic root of 398978107 is about 736.1783169814.

The spelling of 398978107 in words is "three hundred ninety-eight million, nine hundred seventy-eight thousand, one hundred seven".