78426322209 has 27 divisors (see below), whose sum is σ = 114031272537. Its totient is φ = 51940877184.

The previous prime is 78426322199. The next prime is 78426322223. The reversal of 78426322209 is 90222362487.

The square root of 78426322209 is 280047.

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

78426322209 is a `hidden beast` number, since 7 + 8 + 4 + 2 + 632 + 2 + 2 + 0 + 9 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 24759966609 + 53666355600 = 157353^2 + 231660^2 .

It is not a de Polignac number, because 78426322209 - 2¹³ = 78426314017 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (78426321209) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 232718889 + ... + 232719225.

Almost surely, 2^78426322209 is an apocalyptic number.

78426322209 is the 280047-th square number.

78426322209 is the 140024-th centered octagonal number.

It is an amenable number.

78426322209 is a deficient number, since it is larger than the sum of its proper divisors (35604950328).

78426322209 is an frugal number, since it uses more digits than its factorization.

78426322209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1234 (or 617 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 45.

The spelling of 78426322209 in words is "seventy-eight billion, four hundred twenty-six million, three hundred twenty-two thousand, two hundred nine".