78013 has 8 divisors (see below), whose sum is σ = 89208. Its totient is φ = 67584.

The previous prime is 78007. The next prime is 78017. The reversal of 78013 is 31087.

78013 = 197² + 198².

It can be written as a sum of positive squares in 4 ways, for example, as 6724 + 71289 = 82^2 + 267^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a 6-Lehmer number, since φ(78013) divides (78013-1)⁶.

It is a cyclic number.

It is not a de Polignac number, because 78013 - 2¹³ = 69821 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 (78017) 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, 45 + ... + 397.

It is an arithmetic number, because the mean of its divisors is an integer number (11151).

2⁷⁸⁰¹³ is an apocalyptic number.

78013 is the 198-th centered square number.

It is an amenable number.

78013 is a deficient number, since it is larger than the sum of its proper divisors (11195).

78013 is a wasteful number, since it uses less digits than its factorization.

78013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 383.

The product of its (nonzero) digits is 168, while the sum is 19.

The square root of 78013 is about 279.3080736391. The cubic root of 78013 is about 42.7289603844.

The spelling of 78013 in words is "seventy-eight thousand, thirteen".