78005749 has 4 divisors (see below), whose sum is σ = 78107436. Its totient is φ = 77904064.

The previous prime is 78005723. The next prime is 78005779. The reversal of 78005749 is 94750087.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 94750087 = 23 ⋅4119569.

It can be written as a sum of positive squares in 2 ways, for example, as 2002225 + 76003524 = 1415^2 + 8718^2 .

It is a cyclic number.

It is not a de Polignac number, because 78005749 - 2⁵ = 78005717 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 (78005779) 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, 49684 + ... + 51229.

It is an arithmetic number, because the mean of its divisors is an integer number (19526859).

Almost surely, 2^78005749 is an apocalyptic number.

It is an amenable number.

78005749 is a deficient number, since it is larger than the sum of its proper divisors (101687).

78005749 is a wasteful number, since it uses less digits than its factorization.

78005749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101686.

The product of its (nonzero) digits is 70560, while the sum is 40.

The square root of 78005749 is about 8832.0863333643. The cubic root of 78005749 is about 427.2763651404.

The spelling of 78005749 in words is "seventy-eight million, five thousand, seven hundred forty-nine".