78661367 has 4 divisors (see below), whose sum is σ = 78775896. Its totient is φ = 78546840.

The previous prime is 78661361. The next prime is 78661393. The reversal of 78661367 is 76316687.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 76316687 = 1021 ⋅74747.

It is a cyclic number.

It is not a de Polignac number, because 78661367 - 2¹⁴ = 78644983 is a prime.

It is a super-2 number, since 2×78661367² = 12375221316617378, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78661361) 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, 56228 + ... + 57609.

It is an arithmetic number, because the mean of its divisors is an integer number (19693974).

Almost surely, 2^78661367 is an apocalyptic number.

78661367 is a deficient number, since it is larger than the sum of its proper divisors (114529).

78661367 is a wasteful number, since it uses less digits than its factorization.

78661367 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114528.

The product of its digits is 254016, while the sum is 44.

The square root of 78661367 is about 8869.1243648965. The cubic root of 78661367 is about 428.4700759325.

The spelling of 78661367 in words is "seventy-eight million, six hundred sixty-one thousand, three hundred sixty-seven".