20409623 has 6 divisors (see below), whose sum is σ = 22100544. Its totient is φ = 18839496.

The previous prime is 20409601. The next prime is 20409643. The reversal of 20409623 is 32690402.

It is not a de Polignac number, because 20409623 - 2¹⁰ = 20408599 is a prime.

It is a super-2 number, since 2×20409623² = 833105422004258, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20409592 and 20409601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20409643) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 60215 + ... + 60552.

It is an arithmetic number, because the mean of its divisors is an integer number (3683424).

Almost surely, 2^20409623 is an apocalyptic number.

20409623 is a deficient number, since it is larger than the sum of its proper divisors (1690921).

20409623 is a wasteful number, since it uses less digits than its factorization.

20409623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120793 (or 120780 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 26.

The square root of 20409623 is about 4517.7010746618. The cubic root of 20409623 is about 273.2823986326.

The spelling of 20409623 in words is "twenty million, four hundred nine thousand, six hundred twenty-three".