20623619 has 2 divisors, whose sum is σ = 20623620. Its totient is φ = 20623618.

The previous prime is 20623609. The next prime is 20623621. The reversal of 20623619 is 91632602.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20623619 is a prime.

It is a super-2 number, since 2×20623619² = 850667321314322, which contains 22 as substring.

Together with 20623621, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 20623591 and 20623600.

It is not a weakly prime, because it can be changed into another prime (20623609) 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, 10311809 + 10311810.

It is an arithmetic number, because the mean of its divisors is an integer number (10311810).

Almost surely, 2^20623619 is an apocalyptic number.

20623619 is a deficient number, since it is larger than the sum of its proper divisors (1).

20623619 is an equidigital number, since it uses as much as digits as its factorization.

20623619 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3888, while the sum is 29.

The square root of 20623619 is about 4541.3234855051. The cubic root of 20623619 is about 274.2342066625.

The spelling of 20623619 in words is "twenty million, six hundred twenty-three thousand, six hundred nineteen".