20156623 has 2 divisors, whose sum is σ = 20156624. Its totient is φ = 20156622.

The previous prime is 20156621. The next prime is 20156627. The reversal of 20156623 is 32665102.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20156623 - 2¹ = 20156621 is a prime.

Together with 20156621, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20156621) 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, 10078311 + 10078312.

It is an arithmetic number, because the mean of its divisors is an integer number (10078312).

Almost surely, 2^20156623 is an apocalyptic number.

20156623 is a deficient number, since it is larger than the sum of its proper divisors (1).

20156623 is an equidigital number, since it uses as much as digits as its factorization.

20156623 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 20156623 is about 4489.6127895399. The cubic root of 20156623 is about 272.1484870838.

The spelling of 20156623 in words is "twenty million, one hundred fifty-six thousand, six hundred twenty-three".