39978398 has 4 divisors (see below), whose sum is σ = 59967600. Its totient is φ = 19989198.

The previous prime is 39978391. The next prime is 39978409. The reversal of 39978398 is 89387993.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 89387993 = 4831 ⋅18503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39978391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9994598 + ... + 9994601.

It is an arithmetic number, because the mean of its divisors is an integer number (14991900).

Almost surely, 2^39978398 is an apocalyptic number.

39978398 is a deficient number, since it is larger than the sum of its proper divisors (19989202).

39978398 is a wasteful number, since it uses less digits than its factorization.

39978398 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19989201.

The product of its digits is 2939328, while the sum is 56.

The square root of 39978398 is about 6322.8473016514. The cubic root of 39978398 is about 341.9336134153.

The spelling of 39978398 in words is "thirty-nine million, nine hundred seventy-eight thousand, three hundred ninety-eight".