77838210025 has 9 divisors (see below), whose sum is σ = 96521110231. Its totient is φ = 62269452040.

The previous prime is 77838210013. The next prime is 77838210113. The reversal of 77838210025 is 52001283877.

The square root of 77838210025 is 278995.

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

It can be written as a sum of positive squares in only one way, i.e., 28021755609 + 49816454416 = 167397^2 + 223196^2 .

It is not a de Polignac number, because 77838210025 - 2¹⁷ = 77838078953 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1367076 + ... + 1422874.

Almost surely, 2^77838210025 is an apocalyptic number.

77838210025 is the 278995-th square number.

77838210025 is the 139498-th centered octagonal number.

It is an amenable number.

77838210025 is a deficient number, since it is larger than the sum of its proper divisors (18682900206).

77838210025 is an frugal number, since it uses more digits than its factorization.

77838210025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111608 (or 55804 counting only the distinct ones).

The product of its (nonzero) digits is 188160, while the sum is 43.

The spelling of 77838210025 in words is "seventy-seven billion, eight hundred thirty-eight million, two hundred ten thousand, twenty-five".