78106405 has 8 divisors (see below), whose sum is σ = 100937592. Its totient is φ = 57678528.

The previous prime is 78106393. The next prime is 78106409. The reversal of 78106405 is 50460187.

It can be written as a sum of positive squares in 4 ways, for example, as 349281 + 77757124 = 591^2 + 8818^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 78106405 - 2⁵ = 78106373 is a prime.

It is a super-2 number, since 2×78106405² = 12201221004048050, 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 (78106409) 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, 600754 + ... + 600883.

It is an arithmetic number, because the mean of its divisors is an integer number (12617199).

Almost surely, 2^78106405 is an apocalyptic number.

It is an amenable number.

78106405 is a deficient number, since it is larger than the sum of its proper divisors (22831187).

78106405 is a wasteful number, since it uses less digits than its factorization.

78106405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1201655.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 78106405 is about 8837.7828101849. The cubic root of 78106405 is about 427.4600671750.

The spelling of 78106405 in words is "seventy-eight million, one hundred six thousand, four hundred five".