78629389 has 4 divisors (see below), whose sum is σ = 78780256. Its totient is φ = 78478524.

The previous prime is 78629377. The next prime is 78629393. The reversal of 78629389 is 98392687.

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.

It is a cyclic number.

It is not a de Polignac number, because 78629389 - 2⁹ = 78628877 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 (78629339) 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, 74649 + ... + 75694.

It is an arithmetic number, because the mean of its divisors is an integer number (19695064).

Almost surely, 2^78629389 is an apocalyptic number.

It is an amenable number.

78629389 is a deficient number, since it is larger than the sum of its proper divisors (150867).

78629389 is a wasteful number, since it uses less digits than its factorization.

78629389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150866.

The product of its digits is 1306368, while the sum is 52.

The square root of 78629389 is about 8867.3214106629. The cubic root of 78629389 is about 428.4120064561.

The spelling of 78629389 in words is "seventy-eight million, six hundred twenty-nine thousand, three hundred eighty-nine".