101970809 has 2 divisors, whose sum is σ = 101970810. Its totient is φ = 101970808.

The previous prime is 101970797. The next prime is 101970857. The reversal of 101970809 is 908079101.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 101445184 + 525625 = 10072^2 + 725^2 .

It is a cyclic number.

It is not a de Polignac number, because 101970809 - 2⁸ = 101970553 is a prime.

It is a super-2 number, since 2×101970809² = 20796091776228962, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (101970859) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50985404 + 50985405.

It is an arithmetic number, because the mean of its divisors is an integer number (50985405).

Almost surely, 2^101970809 is an apocalyptic number.

It is an amenable number.

101970809 is a deficient number, since it is larger than the sum of its proper divisors (1).

101970809 is an equidigital number, since it uses as much as digits as its factorization.

101970809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4536, while the sum is 35.

The square root of 101970809 is about 10098.0596651040. The cubic root of 101970809 is about 467.1882967045.

The spelling of 101970809 in words is "one hundred one million, nine hundred seventy thousand, eight hundred nine".