78607861 has 4 divisors (see below), whose sum is σ = 78664300. Its totient is φ = 78551424.

The previous prime is 78607843. The next prime is 78607873. The reversal of 78607861 is 16870687.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16870687 = 79 ⋅213553.

It can be written as a sum of positive squares in 2 ways, for example, as 31080625 + 47527236 = 5575^2 + 6894^2 .

It is a cyclic number.

It is not a de Polignac number, because 78607861 - 2¹³ = 78599669 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 (78607801) 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, 26076 + ... + 28933.

It is an arithmetic number, because the mean of its divisors is an integer number (19666075).

Almost surely, 2^78607861 is an apocalyptic number.

It is an amenable number.

78607861 is a deficient number, since it is larger than the sum of its proper divisors (56439).

78607861 is a wasteful number, since it uses less digits than its factorization.

78607861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56438.

The product of its (nonzero) digits is 112896, while the sum is 43.

The square root of 78607861 is about 8866.1074322388. The cubic root of 78607861 is about 428.3729044713.

The spelling of 78607861 in words is "seventy-eight million, six hundred seven thousand, eight hundred sixty-one".