78185296640025 has 81 divisors (see below), whose sum is σ = 145041118901341. Its totient is φ = 40258953698880.

The previous prime is 78185296639999. The next prime is 78185296640093. The reversal of 78185296640025 is 52004669258187.

The square root of 78185296640025 is 8842245.

It is a perfect power (a square), and thus also a powerful number.

78185296640025 is a `hidden beast` number, since 7 + 8 + 1 + 8 + 529 + 66 + 40 + 0 + 2 + 5 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1074699202329 + 77110597437696 = 1036677^2 + 8781264^2 .

It is not a de Polignac number, because 78185296640025 - 2⁷ = 78185296639897 is a prime.

It is a super-2 number, since 2×78185296640025² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 3846366412 + ... + 3846386738.

Almost surely, 2^{78185296640025} is an apocalyptic number.

78185296640025 is a gapful number since it is divisible by the number (75) formed by its first and last digit.

78185296640025 is the 8842245-th square number.

78185296640025 is the 4421123-rd centered octagonal number.

It is an amenable number.

78185296640025 is a deficient number, since it is larger than the sum of its proper divisors (66855822261316).

78185296640025 is an frugal number, since it uses more digits than its factorization.

78185296640025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40728 (or 20364 counting only the distinct ones).

The product of its (nonzero) digits is 58060800, while the sum is 63.

The spelling of 78185296640025 in words is "seventy-eight trillion, one hundred eighty-five billion, two hundred ninety-six million, six hundred forty thousand, twenty-five".