21350001 has 4 divisors (see below), whose sum is σ = 28466672. Its totient is φ = 14233332.

The previous prime is 21349997. The next prime is 21350009. The reversal of 21350001 is 10005312.

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.

It is not a de Polignac number, because 21350001 - 2² = 21349997 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21350009) 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, 3558331 + ... + 3558336.

It is an arithmetic number, because the mean of its divisors is an integer number (7116668).

Almost surely, 2^21350001 is an apocalyptic number.

It is an amenable number.

21350001 is a deficient number, since it is larger than the sum of its proper divisors (7116671).

21350001 is an equidigital number, since it uses as much as digits as its factorization.

21350001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7116670.

The product of its (nonzero) digits is 30, while the sum is 12.

The square root of 21350001 is about 4620.6061290701. The cubic root of 21350001 is about 277.4167204038.

Adding to 21350001 its reverse (10005312), we get a palindrome (31355313).

The spelling of 21350001 in words is "twenty-one million, three hundred fifty thousand, one".