101660581 has 4 divisors (see below), whose sum is σ = 110902464. Its totient is φ = 92418700.

The previous prime is 101660551. The next prime is 101660591. The reversal of 101660581 is 185066101.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 185066101 = 11 ⋅16824191.

It is not a de Polignac number, because 101660581 - 2⁵ = 101660549 is a prime.

It is a super-2 number, since 2×101660581² = 20669747458515122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (101660521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4620925 + ... + 4620946.

It is an arithmetic number, because the mean of its divisors is an integer number (27725616).

Almost surely, 2^101660581 is an apocalyptic number.

101660581 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

101660581 is a deficient number, since it is larger than the sum of its proper divisors (9241883).

101660581 is an equidigital number, since it uses as much as digits as its factorization.

101660581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9241882.

The product of its (nonzero) digits is 1440, while the sum is 28.

The square root of 101660581 is about 10082.6871914188. The cubic root of 101660581 is about 466.7140364046.

The spelling of 101660581 in words is "one hundred one million, six hundred sixty thousand, five hundred eighty-one".