78621 has 8 divisors (see below), whose sum is σ = 106560. Its totient is φ = 51552.

The previous prime is 78607. The next prime is 78623. The reversal of 78621 is 12687.

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

It is not a de Polignac number, because 78621 - 2¹³ = 70429 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 78591 and 78600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78623) 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, 40 + ... + 398.

It is an arithmetic number, because the mean of its divisors is an integer number (13320).

2⁷⁸⁶²¹ is an apocalyptic number.

It is an amenable number.

78621 is a deficient number, since it is larger than the sum of its proper divisors (27939).

78621 is a wasteful number, since it uses less digits than its factorization.

78621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 435.

The product of its digits is 672, while the sum is 24.

The square root of 78621 is about 280.3943651360. The cubic root of 78621 is about 42.8396770100.

The spelling of 78621 in words is "seventy-eight thousand, six hundred twenty-one".