21401123 has 2 divisors, whose sum is σ = 21401124. Its totient is φ = 21401122.

The previous prime is 21401119. The next prime is 21401137. The reversal of 21401123 is 32110412.

It is an a-pointer prime, because the next prime (21401137) can be obtained adding 21401123 to its sum of digits (14).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21401123 - 2² = 21401119 is a prime.

It is a super-2 number, since 2×21401123² = 916016131322258, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21401098 and 21401107.

It is not a weakly prime, because it can be changed into another prime (21401323) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10700561 + 10700562.

It is an arithmetic number, because the mean of its divisors is an integer number (10700562).

Almost surely, 2^21401123 is an apocalyptic number.

21401123 is a deficient number, since it is larger than the sum of its proper divisors (1).

21401123 is an equidigital number, since it uses as much as digits as its factorization.

21401123 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 21401123 is about 4626.1347797054. The cubic root of 21401123 is about 277.6379661868.

Adding to 21401123 its reverse (32110412), we get a palindrome (53511535).

The spelling of 21401123 in words is "twenty-one million, four hundred one thousand, one hundred twenty-three".