78955909 has 2 divisors, whose sum is σ = 78955910. Its totient is φ = 78955908.

The previous prime is 78955901. The next prime is 78955957. The reversal of 78955909 is 90955987.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 76615009 + 2340900 = 8753^2 + 1530^2 .

It is a cyclic number.

It is not a de Polignac number, because 78955909 - 2³ = 78955901 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78955901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39477954 + 39477955.

It is an arithmetic number, because the mean of its divisors is an integer number (39477955).

Almost surely, 2^78955909 is an apocalyptic number.

It is an amenable number.

78955909 is a deficient number, since it is larger than the sum of its proper divisors (1).

78955909 is an equidigital number, since it uses as much as digits as its factorization.

78955909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1020600, while the sum is 52.

The square root of 78955909 is about 8885.7137586128. The cubic root of 78955909 is about 429.0042019211.

The spelling of 78955909 in words is "seventy-eight million, nine hundred fifty-five thousand, nine hundred nine".