101920109 has 2 divisors, whose sum is σ = 101920110. Its totient is φ = 101920108.

The previous prime is 101920097. The next prime is 101920139. The reversal of 101920109 is 901029101.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 101566084 + 354025 = 10078^2 + 595^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-101920109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (101920139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50960054 + 50960055.

It is an arithmetic number, because the mean of its divisors is an integer number (50960055).

Almost surely, 2^101920109 is an apocalyptic number.

It is an amenable number.

101920109 is a deficient number, since it is larger than the sum of its proper divisors (1).

101920109 is an equidigital number, since it uses as much as digits as its factorization.

101920109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162, while the sum is 23.

The square root of 101920109 is about 10095.5489697193. The cubic root of 101920109 is about 467.1108550209.

The spelling of 101920109 in words is "one hundred one million, nine hundred twenty thousand, one hundred nine".