101813581 has 2 divisors, whose sum is σ = 101813582. Its totient is φ = 101813580.

The previous prime is 101813573. The next prime is 101813587. The reversal of 101813581 is 185318101.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51984100 + 49829481 = 7210^2 + 7059^2 .

It is an emirp because it is prime and its reverse (185318101) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 101813581 - 2³ = 101813573 is a prime.

It is a super-2 number, since 2×101813581² = 20732010552087122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (101813587) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50906790 + 50906791.

It is an arithmetic number, because the mean of its divisors is an integer number (50906791).

Almost surely, 2^101813581 is an apocalyptic number.

It is an amenable number.

101813581 is a deficient number, since it is larger than the sum of its proper divisors (1).

101813581 is an equidigital number, since it uses as much as digits as its factorization.

101813581 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 960, while the sum is 28.

The square root of 101813581 is about 10090.2716018946. The cubic root of 101813581 is about 466.9480551822.

The spelling of 101813581 in words is "one hundred one million, eight hundred thirteen thousand, five hundred eighty-one".