20256149 has 2 divisors, whose sum is σ = 20256150. Its totient is φ = 20256148.

The previous prime is 20256143. The next prime is 20256151. The reversal of 20256149 is 94165202.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15547249 + 4708900 = 3943^2 + 2170^2 .

It is a cyclic number.

It is not a de Polignac number, because 20256149 - 2¹² = 20252053 is a prime.

Together with 20256151, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20256143) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10128074 + 10128075.

It is an arithmetic number, because the mean of its divisors is an integer number (10128075).

Almost surely, 2^20256149 is an apocalyptic number.

It is an amenable number.

20256149 is a deficient number, since it is larger than the sum of its proper divisors (1).

20256149 is an equidigital number, since it uses as much as digits as its factorization.

20256149 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 20256149 is about 4500.6831703643. The cubic root of 20256149 is about 272.5956749588.

The spelling of 20256149 in words is "twenty million, two hundred fifty-six thousand, one hundred forty-nine".