21230401 has 2 divisors, whose sum is σ = 21230402. Its totient is φ = 21230400.

The previous prime is 21230389. The next prime is 21230431. The reversal of 21230401 is 10403212.

21230401 is nontrivially palindromic in base 16.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17007376 + 4223025 = 4124^2 + 2055^2 .

It is a cyclic number.

It is not a de Polignac number, because 21230401 - 2⁷ = 21230273 is a prime.

It is not a weakly prime, because it can be changed into another prime (21230431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10615200 + 10615201.

It is an arithmetic number, because the mean of its divisors is an integer number (10615201).

Almost surely, 2^21230401 is an apocalyptic number.

It is an amenable number.

21230401 is a deficient number, since it is larger than the sum of its proper divisors (1).

21230401 is an equidigital number, since it uses as much as digits as its factorization.

21230401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 21230401 is about 4607.6459282371. The cubic root of 21230401 is about 276.8977323216.

Adding to 21230401 its reverse (10403212), we get a palindrome (31633613).

The spelling of 21230401 in words is "twenty-one million, two hundred thirty thousand, four hundred one".