78923649 has 16 divisors (see below), whose sum is σ = 125494272. Its totient is φ = 43138128.

The previous prime is 78923629. The next prime is 78923653. The reversal of 78923649 is 94632987.

It is not a de Polignac number, because 78923649 - 2²⁵ = 45369217 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 78923598 and 78923607.

It is not an unprimeable number, because it can be changed into a prime (78923629) 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 15 ways as a sum of consecutive naturals, for example, 81219 + ... + 82184.

It is an arithmetic number, because the mean of its divisors is an integer number (7843392).

Almost surely, 2^78923649 is an apocalyptic number.

It is an amenable number.

78923649 is a deficient number, since it is larger than the sum of its proper divisors (46570623).

78923649 is a wasteful number, since it uses less digits than its factorization.

78923649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163436.

The product of its digits is 653184, while the sum is 48.

The square root of 78923649 is about 8883.8982997331. The cubic root of 78923649 is about 428.9457660968.

The spelling of 78923649 in words is "seventy-eight million, nine hundred twenty-three thousand, six hundred forty-nine".