21098663 has 2 divisors, whose sum is σ = 21098664. Its totient is φ = 21098662.

The previous prime is 21098657. The next prime is 21098669. The reversal of 21098663 is 36689012.

It is a balanced prime because it is at equal distance from previous prime (21098657) and next prime (21098669).

It is a cyclic number.

It is not a de Polignac number, because 21098663 - 2⁴ = 21098647 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21098669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10549331 + 10549332.

It is an arithmetic number, because the mean of its divisors is an integer number (10549332).

Almost surely, 2^21098663 is an apocalyptic number.

21098663 is a deficient number, since it is larger than the sum of its proper divisors (1).

21098663 is an equidigital number, since it uses as much as digits as its factorization.

21098663 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 35.

The square root of 21098663 is about 4593.3280962718. The cubic root of 21098663 is about 276.3238121660.

The spelling of 21098663 in words is "twenty-one million, ninety-eight thousand, six hundred sixty-three".