78243645 has 8 divisors (see below), whose sum is σ = 125189856. Its totient is φ = 41729936.

The previous prime is 78243629. The next prime is 78243647. The reversal of 78243645 is 54634287.

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 78243645 - 2⁴ = 78243629 is a prime.

It is a super-2 number, since 2×78243645² = 12244135965772050, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78243647) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2608107 + ... + 2608136.

It is an arithmetic number, because the mean of its divisors is an integer number (15648732).

Almost surely, 2^78243645 is an apocalyptic number.

It is an amenable number.

78243645 is a deficient number, since it is larger than the sum of its proper divisors (46946211).

78243645 is a wasteful number, since it uses less digits than its factorization.

78243645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5216251.

The product of its digits is 161280, while the sum is 39.

The square root of 78243645 is about 8845.5437933459. The cubic root of 78243645 is about 427.7102826490.

The spelling of 78243645 in words is "seventy-eight million, two hundred forty-three thousand, six hundred forty-five".