78769389 has 4 divisors (see below), whose sum is σ = 105025856. Its totient is φ = 52512924.

The previous prime is 78769351. The next prime is 78769403. The reversal of 78769389 is 98396787.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 98396787 = 3 ⋅32798929.

It is not a de Polignac number, because 78769389 - 2²¹ = 76672237 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78769489) 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, 13128229 + ... + 13128234.

It is an arithmetic number, because the mean of its divisors is an integer number (26256464).

Almost surely, 2^78769389 is an apocalyptic number.

It is an amenable number.

78769389 is a deficient number, since it is larger than the sum of its proper divisors (26256467).

78769389 is a wasteful number, since it uses less digits than its factorization.

78769389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26256466.

The product of its digits is 4572288, while the sum is 57.

The square root of 78769389 is about 8875.2120538047. The cubic root of 78769389 is about 428.6661189026. Note that the first 3 decimals are identical.

The spelling of 78769389 in words is "seventy-eight million, seven hundred sixty-nine thousand, three hundred eighty-nine".