21460181 has 2 divisors, whose sum is σ = 21460182. Its totient is φ = 21460180.

The previous prime is 21460163. The next prime is 21460207. The reversal of 21460181 is 18106412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10956100 + 10504081 = 3310^2 + 3241^2 .

It is a cyclic number.

It is not a de Polignac number, because 21460181 - 2²² = 17265877 is a prime.

It is a super-2 number, since 2×21460181² = 921078737105522, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21460141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10730090 + 10730091.

It is an arithmetic number, because the mean of its divisors is an integer number (10730091).

Almost surely, 2^21460181 is an apocalyptic number.

It is an amenable number.

21460181 is a deficient number, since it is larger than the sum of its proper divisors (1).

21460181 is an equidigital number, since it uses as much as digits as its factorization.

21460181 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 384, while the sum is 23.

The square root of 21460181 is about 4632.5134646323. The cubic root of 21460181 is about 277.8931192054.

Adding to 21460181 its reverse (18106412), we get a palindrome (39566593).

The spelling of 21460181 in words is "twenty-one million, four hundred sixty thousand, one hundred eighty-one".