101806643 has 4 divisors (see below), whose sum is σ = 101829840. Its totient is φ = 101783448.

The previous prime is 101806637. The next prime is 101806669. The reversal of 101806643 is 346608101.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 346608101 = 7 ⋅49515443.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-101806643 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (101806613) 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, 2780 + ... + 14537.

It is an arithmetic number, because the mean of its divisors is an integer number (25457460).

Almost surely, 2^101806643 is an apocalyptic number.

101806643 is a deficient number, since it is larger than the sum of its proper divisors (23197).

101806643 is an equidigital number, since it uses as much as digits as its factorization.

101806643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23196.

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 101806643 is about 10089.9277995435. The cubic root of 101806643 is about 466.9374483484.

The spelling of 101806643 in words is "one hundred one million, eight hundred six thousand, six hundred forty-three".