101025809 has 2 divisors, whose sum is σ = 101025810. Its totient is φ = 101025808.

The previous prime is 101025787. The next prime is 101025817. The reversal of 101025809 is 908520101.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 97614400 + 3411409 = 9880^2 + 1847^2 .

It is an emirp because it is prime and its reverse (908520101) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 101025809 - 2²⁰ = 99977233 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (101025839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50512904 + 50512905.

It is an arithmetic number, because the mean of its divisors is an integer number (50512905).

Almost surely, 2^101025809 is an apocalyptic number.

It is an amenable number.

101025809 is a deficient number, since it is larger than the sum of its proper divisors (1).

101025809 is an equidigital number, since it uses as much as digits as its factorization.

101025809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 720, while the sum is 26.

The square root of 101025809 is about 10051.1595848439. The cubic root of 101025809 is about 465.7406149791.

The spelling of 101025809 in words is "one hundred one million, twenty-five thousand, eight hundred nine".