100021601 has 4 divisors (see below), whose sum is σ = 100259604. Its totient is φ = 99783600.

The previous prime is 100021589. The next prime is 100021627. The reversal of 100021601 is 106120001.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 421201 + 99600400 = 649^2 + 9980^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-100021601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (100021631) 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, 118370 + ... + 119211.

It is an arithmetic number, because the mean of its divisors is an integer number (25064901).

Almost surely, 2^100021601 is an apocalyptic number.

It is an amenable number.

100021601 is a deficient number, since it is larger than the sum of its proper divisors (238003).

100021601 is an equidigital number, since it uses as much as digits as its factorization.

100021601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238002.

The product of its (nonzero) digits is 12, while the sum is 11.

The square root of 100021601 is about 10001.0799916809. The cubic root of 100021601 is about 464.1923019419.

Adding to 100021601 its reverse (106120001), we get a palindrome (206141602).

The spelling of 100021601 in words is "one hundred million, twenty-one thousand, six hundred one".