20156369 has 2 divisors, whose sum is σ = 20156370. Its totient is φ = 20156368.

The previous prime is 20156333. The next prime is 20156401. The reversal of 20156369 is 96365102.

It is a happy number.

It is an a-pointer prime, because the next prime (20156401) can be obtained adding 20156369 to its sum of digits (32).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16096144 + 4060225 = 4012^2 + 2015^2 .

It is a cyclic number.

It is not a de Polignac number, because 20156369 - 2²⁰ = 19107793 is a prime.

It is a super-2 number, since 2×20156369² = 812558422528322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (20156329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10078184 + 10078185.

It is an arithmetic number, because the mean of its divisors is an integer number (10078185).

Almost surely, 2^20156369 is an apocalyptic number.

It is an amenable number.

20156369 is a deficient number, since it is larger than the sum of its proper divisors (1).

20156369 is an equidigital number, since it uses as much as digits as its factorization.

20156369 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9720, while the sum is 32.

The square root of 20156369 is about 4489.5845019333. The cubic root of 20156369 is about 272.1473439358.

The spelling of 20156369 in words is "twenty million, one hundred fifty-six thousand, three hundred sixty-nine".