128492101 has 4 divisors (see below), whose sum is σ = 128700972. Its totient is φ = 128283232.

The previous prime is 128492071. The next prime is 128492113. The reversal of 128492101 is 101294821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 101294821 = 67 ⋅1511863.

It can be written as a sum of positive squares in 2 ways, for example, as 5171076 + 123321025 = 2274^2 + 11105^2 .

It is a cyclic number.

It is not a de Polignac number, because 128492101 - 2⁷ = 128491973 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 128492101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128492201) 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, 103510 + ... + 104743.

It is an arithmetic number, because the mean of its divisors is an integer number (32175243).

Almost surely, 2^128492101 is an apocalyptic number.

It is an amenable number.

128492101 is a deficient number, since it is larger than the sum of its proper divisors (208871).

128492101 is an equidigital number, since it uses as much as digits as its factorization.

128492101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208870.

The product of its (nonzero) digits is 1152, while the sum is 28.

The square root of 128492101 is about 11335.4356334461. The cubic root of 128492101 is about 504.6134361584.

The spelling of 128492101 in words is "one hundred twenty-eight million, four hundred ninety-two thousand, one hundred one".