78257265025 has 9 divisors (see below), whose sum is σ = 97040743081. Its totient is φ = 62604693040.

The previous prime is 78257265011. The next prime is 78257265041. The reversal of 78257265025 is 52056275287.

The square root of 78257265025 is 279745.

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

It can be written as a sum of positive squares in 4 ways, for example, as 11928353089 + 66328911936 = 109217^2 + 257544^2 .

It is not a de Polignac number, because 78257265025 - 2⁹ = 78257264513 is a prime.

It is a super-2 number, since 2×78257265025² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 78257265025.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1370751 + ... + 1426699.

Almost surely, 2^78257265025 is an apocalyptic number.

78257265025 is the 279745-th square number.

78257265025 is the 139873-rd centered octagonal number.

It is an amenable number.

78257265025 is a deficient number, since it is larger than the sum of its proper divisors (18783478056).

78257265025 is an frugal number, since it uses more digits than its factorization.

78257265025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111908 (or 55954 counting only the distinct ones).

The product of its (nonzero) digits is 2352000, while the sum is 49.

Multiplying 78257265025 by its sum of digits (49), we get a square (3834605986225 = 1958215²).

The spelling of 78257265025 in words is "seventy-eight billion, two hundred fifty-seven million, two hundred sixty-five thousand, twenty-five".