78861445 has 8 divisors (see below), whose sum is σ = 101913336. Its totient is φ = 58236096.

The previous prime is 78861443. The next prime is 78861449. The reversal of 78861445 is 54416887.

It can be written as a sum of positive squares in 4 ways, for example, as 9622404 + 69239041 = 3102^2 + 8321^2 .

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 78861445 - 2¹ = 78861443 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 (78861443) 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, 606562 + ... + 606691.

It is an arithmetic number, because the mean of its divisors is an integer number (12739167).

Almost surely, 2^78861445 is an apocalyptic number.

It is an amenable number.

78861445 is a deficient number, since it is larger than the sum of its proper divisors (23051891).

78861445 is a wasteful number, since it uses less digits than its factorization.

78861445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1213271.

The product of its digits is 215040, while the sum is 43.

The square root of 78861445 is about 8880.3966690683. The cubic root of 78861445 is about 428.8330446852.

The spelling of 78861445 in words is "seventy-eight million, eight hundred sixty-one thousand, four hundred forty-five".