20905436 has 12 divisors (see below), whose sum is σ = 38175312. Its totient is φ = 9998208.

The previous prime is 20905429. The next prime is 20905499. The reversal of 20905436 is 63450902.

It is a junction number, because it is equal to n+sod(n) for n = 20905399 and 20905408.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113525 + ... + 113708.

It is an arithmetic number, because the mean of its divisors is an integer number (3181276).

Almost surely, 2^20905436 is an apocalyptic number.

It is an amenable number.

20905436 is a deficient number, since it is larger than the sum of its proper divisors (17269876).

20905436 is a wasteful number, since it uses less digits than its factorization.

20905436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 227260 (or 227258 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 29.

The square root of 20905436 is about 4572.2462750819. The cubic root of 20905436 is about 275.4776755812.

The spelling of 20905436 in words is "twenty million, nine hundred five thousand, four hundred thirty-six".