100523021 has 4 divisors (see below), whose sum is σ = 102974844. Its totient is φ = 98071200.

The previous prime is 100523009. The next prime is 100523039. The reversal of 100523021 is 120325001.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 120325001 = 61 ⋅1972541.

It can be written as a sum of positive squares in 2 ways, for example, as 23872996 + 76650025 = 4886^2 + 8755^2 .

It is a cyclic number.

It is not a de Polignac number, because 100523021 - 2¹⁰ = 100521997 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 100522987 and 100523005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100523221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1225850 + ... + 1225931.

It is an arithmetic number, because the mean of its divisors is an integer number (25743711).

Almost surely, 2^100523021 is an apocalyptic number.

It is an amenable number.

100523021 is a deficient number, since it is larger than the sum of its proper divisors (2451823).

100523021 is an equidigital number, since it uses as much as digits as its factorization.

100523021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2451822.

The product of its (nonzero) digits is 60, while the sum is 14.

The square root of 100523021 is about 10026.1169452585. The cubic root of 100523021 is about 464.9666928007.

Adding to 100523021 its reverse (120325001), we get a palindrome (220848022).

The spelling of 100523021 in words is "one hundred million, five hundred twenty-three thousand, twenty-one".