21401053 has 2 divisors, whose sum is σ = 21401054. Its totient is φ = 21401052.

The previous prime is 21401047. The next prime is 21401069. The reversal of 21401053 is 35010412.

It is an a-pointer prime, because the next prime (21401069) can be obtained adding 21401053 to its sum of digits (16).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21187609 + 213444 = 4603^2 + 462^2 .

It is a cyclic number.

It is not a de Polignac number, because 21401053 - 2¹⁷ = 21269981 is a prime.

It is a plaindrome in base 16.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21401953) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10700526 + 10700527.

It is an arithmetic number, because the mean of its divisors is an integer number (10700527).

Almost surely, 2^21401053 is an apocalyptic number.

It is an amenable number.

21401053 is a deficient number, since it is larger than the sum of its proper divisors (1).

21401053 is an equidigital number, since it uses as much as digits as its factorization.

21401053 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 21401053 is about 4626.1272139880. The cubic root of 21401053 is about 277.6376634818.

Adding to 21401053 its reverse (35010412), we get a palindrome (56411465).

The spelling of 21401053 in words is "twenty-one million, four hundred one thousand, fifty-three".