91028101 has 4 divisors (see below), whose sum is σ = 91723104. Its totient is φ = 90333100.

The previous prime is 91028099. The next prime is 91028131. The reversal of 91028101 is 10182019.

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: 10182019 = 191 ⋅53309.

It is a cyclic number.

It is not a de Polignac number, because 91028101 - 2¹ = 91028099 is a prime.

It is a super-2 number, since 2×91028101² = 16572230343332402, 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 (91028131) 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, 347305 + ... + 347566.

It is an arithmetic number, because the mean of its divisors is an integer number (22930776).

Almost surely, 2^91028101 is an apocalyptic number.

It is an amenable number.

91028101 is a deficient number, since it is larger than the sum of its proper divisors (695003).

91028101 is a wasteful number, since it uses less digits than its factorization.

91028101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 695002.

The product of its (nonzero) digits is 144, while the sum is 22.

The square root of 91028101 is about 9540.8647930887. The cubic root of 91028101 is about 449.8404389027.

The spelling of 91028101 in words is "ninety-one million, twenty-eight thousand, one hundred one".