78212385 has 40 divisors (see below), whose sum is σ = 141526440. Its totient is φ = 41319936.

The previous prime is 78212377. The next prime is 78212401. The reversal of 78212385 is 58321287.

It can be written as a sum of positive squares in 4 ways, for example, as 2313441 + 75898944 = 1521^2 + 8712^2 .

It is not a de Polignac number, because 78212385 - 2³ = 78212377 is a prime.

It is a super-2 number, since 2×78212385² = 12234354334776450, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 44911 + ... + 46619.

It is an arithmetic number, because the mean of its divisors is an integer number (3538161).

Almost surely, 2^78212385 is an apocalyptic number.

It is an amenable number.

78212385 is a deficient number, since it is larger than the sum of its proper divisors (63314055).

78212385 is a wasteful number, since it uses less digits than its factorization.

78212385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1839 (or 1830 counting only the distinct ones).

The product of its digits is 26880, while the sum is 36.

The square root of 78212385 is about 8843.7766254016. The cubic root of 78212385 is about 427.6533152774.

The spelling of 78212385 in words is "seventy-eight million, two hundred twelve thousand, three hundred eighty-five".