21102853 has 2 divisors, whose sum is σ = 21102854. Its totient is φ = 21102852.

The previous prime is 21102821. The next prime is 21102869. The reversal of 21102853 is 35820112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20223009 + 879844 = 4497^2 + 938^2 .

It is a cyclic number.

It is not a de Polignac number, because 21102853 - 2⁵ = 21102821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21102883) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10551426 + 10551427.

It is an arithmetic number, because the mean of its divisors is an integer number (10551427).

Almost surely, 2^21102853 is an apocalyptic number.

It is an amenable number.

21102853 is a deficient number, since it is larger than the sum of its proper divisors (1).

21102853 is an equidigital number, since it uses as much as digits as its factorization.

21102853 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 21102853 is about 4593.7841699409. The cubic root of 21102853 is about 276.3421027427.

Adding to 21102853 its reverse (35820112), we get a palindrome (56922965).

The spelling of 21102853 in words is "twenty-one million, one hundred two thousand, eight hundred fifty-three".