21802159 has 2 divisors, whose sum is σ = 21802160. Its totient is φ = 21802158.

The previous prime is 21802141. The next prime is 21802189. The reversal of 21802159 is 95120812.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21802159 - 2¹⁷ = 21671087 is a prime.

It is a super-2 number, since 2×21802159² = 950668274122562, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21802129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10901079 + 10901080.

It is an arithmetic number, because the mean of its divisors is an integer number (10901080).

Almost surely, 2^21802159 is an apocalyptic number.

21802159 is a deficient number, since it is larger than the sum of its proper divisors (1).

21802159 is an equidigital number, since it uses as much as digits as its factorization.

21802159 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1440, while the sum is 28.

The square root of 21802159 is about 4669.2782097451. The cubic root of 21802159 is about 279.3614658615.

The spelling of 21802159 in words is "twenty-one million, eight hundred two thousand, one hundred fifty-nine".