101428109 has 4 divisors (see below), whose sum is σ = 104925660. Its totient is φ = 97930560.

The previous prime is 101428081. The next prime is 101428121. The reversal of 101428109 is 901824101.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 901824101 = 23011 ⋅39191.

It can be written as a sum of positive squares in 2 ways, for example, as 72505225 + 28922884 = 8515^2 + 5378^2 .

It is a cyclic number.

It is not a de Polignac number, because 101428109 - 2¹² = 101424013 is a prime.

It is a super-2 number, since 2×101428109² = 20575322590631762, 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 (101428199) 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, 1748732 + ... + 1748789.

It is an arithmetic number, because the mean of its divisors is an integer number (26231415).

Almost surely, 2^101428109 is an apocalyptic number.

It is an amenable number.

101428109 is a deficient number, since it is larger than the sum of its proper divisors (3497551).

101428109 is an equidigital number, since it uses as much as digits as its factorization.

101428109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3497550.

The product of its (nonzero) digits is 576, while the sum is 26.

The square root of 101428109 is about 10071.1523173865. The cubic root of 101428109 is about 466.3580126241.

The spelling of 101428109 in words is "one hundred one million, four hundred twenty-eight thousand, one hundred nine".