21710149 has 2 divisors, whose sum is σ = 21710150. Its totient is φ = 21710148.

The previous prime is 21710131. The next prime is 21710153. The reversal of 21710149 is 94101712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21687649 + 22500 = 4657^2 + 150^2 .

It is a cyclic number.

It is not a de Polignac number, because 21710149 - 2⁷ = 21710021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21710159) 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, 10855074 + 10855075.

It is an arithmetic number, because the mean of its divisors is an integer number (10855075).

Almost surely, 2^21710149 is an apocalyptic number.

It is an amenable number.

21710149 is a deficient number, since it is larger than the sum of its proper divisors (1).

21710149 is an equidigital number, since it uses as much as digits as its factorization.

21710149 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 504, while the sum is 25.

The square root of 21710149 is about 4659.4150920475. The cubic root of 21710149 is about 278.9679223836.

The spelling of 21710149 in words is "twenty-one million, seven hundred ten thousand, one hundred forty-nine".