100642409 has 4 divisors (see below), whose sum is σ = 115019904. Its totient is φ = 86264916.

The previous prime is 100642387. The next prime is 100642471. The reversal of 100642409 is 904246001.

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: 904246001 = 113 ⋅8002177.

It is a cyclic number.

It is not a de Polignac number, because 100642409 - 2²⁰ = 99593833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (100642609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7188737 + ... + 7188750.

It is an arithmetic number, because the mean of its divisors is an integer number (28754976).

Almost surely, 2^100642409 is an apocalyptic number.

It is an amenable number.

100642409 is a deficient number, since it is larger than the sum of its proper divisors (14377495).

100642409 is an equidigital number, since it uses as much as digits as its factorization.

100642409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14377494.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 100642409 is about 10032.0690288694. The cubic root of 100642409 is about 465.1506953673.

The spelling of 100642409 in words is "one hundred million, six hundred forty-two thousand, four hundred nine".