21959029 has 2 divisors, whose sum is σ = 21959030. Its totient is φ = 21959028.

The previous prime is 21959017. The next prime is 21959051. The reversal of 21959029 is 92095912.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13490929 + 8468100 = 3673^2 + 2910^2 .

It is a cyclic number.

It is not a de Polignac number, because 21959029 - 2⁷ = 21958901 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21959009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10979514 + 10979515.

It is an arithmetic number, because the mean of its divisors is an integer number (10979515).

Almost surely, 2^21959029 is an apocalyptic number.

It is an amenable number.

21959029 is a deficient number, since it is larger than the sum of its proper divisors (1).

21959029 is an equidigital number, since it uses as much as digits as its factorization.

21959029 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14580, while the sum is 37.

The square root of 21959029 is about 4686.0462012234. The cubic root of 21959029 is about 280.0298820149.

The spelling of 21959029 in words is "twenty-one million, nine hundred fifty-nine thousand, twenty-nine".