70725209 has 2 divisors, whose sum is σ = 70725210. Its totient is φ = 70725208.

The previous prime is 70725191. The next prime is 70725223. The reversal of 70725209 is 90252707.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 67190809 + 3534400 = 8197^2 + 1880^2 .

It is an emirp because it is prime and its reverse (90252707) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-70725209 is a prime.

It is not a weakly prime, because it can be changed into another prime (70725269) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35362604 + 35362605.

It is an arithmetic number, because the mean of its divisors is an integer number (35362605).

Almost surely, 2^70725209 is an apocalyptic number.

It is an amenable number.

70725209 is a deficient number, since it is larger than the sum of its proper divisors (1).

70725209 is an equidigital number, since it uses as much as digits as its factorization.

70725209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8820, while the sum is 32.

The square root of 70725209 is about 8409.8281195278. The cubic root of 70725209 is about 413.5468779631.

The spelling of 70725209 in words is "seventy million, seven hundred twenty-five thousand, two hundred nine".