78494869 has 4 divisors (see below), whose sum is σ = 80409420. Its totient is φ = 76580320.

The previous prime is 78494863. The next prime is 78494881. The reversal of 78494869 is 96849487.

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

It can be written as a sum of positive squares in 2 ways, for example, as 40832100 + 37662769 = 6390^2 + 6137^2 .

It is a cyclic number.

It is not a de Polignac number, because 78494869 - 2⁹ = 78494357 is a prime.

It is a super-2 number, since 2×78494869² = 12322888918654322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78494863) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 957214 + ... + 957295.

It is an arithmetic number, because the mean of its divisors is an integer number (20102355).

Almost surely, 2^78494869 is an apocalyptic number.

It is an amenable number.

78494869 is a deficient number, since it is larger than the sum of its proper divisors (1914551).

78494869 is a wasteful number, since it uses less digits than its factorization.

78494869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1914550.

The product of its digits is 3483648, while the sum is 55.

The square root of 78494869 is about 8859.7330095212. The cubic root of 78494869 is about 428.1675563856.

It can be divided in two parts, 78494 and 869, that multiplied together give a palindrome (68211286).

The spelling of 78494869 in words is "seventy-eight million, four hundred ninety-four thousand, eight hundred sixty-nine".