78909201 has 16 divisors (see below), whose sum is σ = 133603200. Its totient is φ = 45090864.

The previous prime is 78909199. The next prime is 78909217. The reversal of 78909201 is 10290987.

It is a happy number.

It is not a de Polignac number, because 78909201 - 2¹ = 78909199 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (78909221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 208566 + ... + 208943.

It is an arithmetic number, because the mean of its divisors is an integer number (8350200).

Almost surely, 2^78909201 is an apocalyptic number.

It is an amenable number.

78909201 is a deficient number, since it is larger than the sum of its proper divisors (54693999).

78909201 is a wasteful number, since it uses less digits than its factorization.

78909201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 417525 (or 417519 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The square root of 78909201 is about 8883.0851059753. The cubic root of 78909201 is about 428.9195897998.

The spelling of 78909201 in words is "seventy-eight million, nine hundred nine thousand, two hundred one".