78183678555545 has 4 divisors (see below), whose sum is σ = 93820414266660. Its totient is φ = 62546942844432.

The previous prime is 78183678555473. The next prime is 78183678555559. The reversal of 78183678555545 is 54555587638187.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 30501629117584 + 47682049437961 = 5522828^2 + 6905219^2 .

It is a cyclic number.

It is not a de Polignac number, because 78183678555545 - 2¹² = 78183678551449 is a prime.

It is a super-2 number, since 2×78183678555545² (a number of 29 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7818367855550 + ... + 7818367855559.

It is an arithmetic number, because the mean of its divisors is an integer number (23455103566665).

Almost surely, 2^{78183678555545} is an apocalyptic number.

It is an amenable number.

78183678555545 is a deficient number, since it is larger than the sum of its proper divisors (15636735711115).

78183678555545 is a wasteful number, since it uses less digits than its factorization.

78183678555545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15636735711114.

The product of its digits is 5644800000, while the sum is 77.

The spelling of 78183678555545 in words is "seventy-eight trillion, one hundred eighty-three billion, six hundred seventy-eight million, five hundred fifty-five thousand, five hundred forty-five".