78253009 has 2 divisors, whose sum is σ = 78253010. Its totient is φ = 78253008.

The previous prime is 78253003. The next prime is 78253033. The reversal of 78253009 is 90035287.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 68013009 + 10240000 = 8247^2 + 3200^2 .

It is a cyclic number.

It is not a de Polignac number, because 78253009 - 2¹⁷ = 78121937 is a prime.

It is a super-2 number, since 2×78253009² = 12247066835108162, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78253003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39126504 + 39126505.

It is an arithmetic number, because the mean of its divisors is an integer number (39126505).

Almost surely, 2^78253009 is an apocalyptic number.

It is an amenable number.

78253009 is a deficient number, since it is larger than the sum of its proper divisors (1).

78253009 is an equidigital number, since it uses as much as digits as its factorization.

78253009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 78253009 is about 8846.0730835778. The cubic root of 78253009 is about 427.7273443938.

The spelling of 78253009 in words is "seventy-eight million, two hundred fifty-three thousand, nine".