78981409 has 8 divisors (see below), whose sum is σ = 86327360. Its totient is φ = 71816976.

The previous prime is 78981407. The next prime is 78981433. The reversal of 78981409 is 90418987.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 78981409 - 2¹ = 78981407 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78981407) 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 in 7 ways as a sum of consecutive naturals, for example, 44469 + ... + 46210.

It is an arithmetic number, because the mean of its divisors is an integer number (10790920).

Almost surely, 2^78981409 is an apocalyptic number.

It is an amenable number.

78981409 is a deficient number, since it is larger than the sum of its proper divisors (7345951).

78981409 is a wasteful number, since it uses less digits than its factorization.

78981409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90759.

The product of its (nonzero) digits is 145152, while the sum is 46.

The square root of 78981409 is about 8887.1485303217. The cubic root of 78981409 is about 429.0503814061.

The spelling of 78981409 in words is "seventy-eight million, nine hundred eighty-one thousand, four hundred nine".