20569956 has 24 divisors (see below), whose sum is σ = 52360224. Its totient is φ = 6233280.

The previous prime is 20569933. The next prime is 20569999. The reversal of 20569956 is 65996502.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 77785 + ... + 78048.

It is an arithmetic number, because the mean of its divisors is an integer number (2181676).

Almost surely, 2^20569956 is an apocalyptic number.

It is an amenable number.

20569956 is an abundant number, since it is smaller than the sum of its proper divisors (31790268).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20569956 is a wasteful number, since it uses less digits than its factorization.

20569956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155851 (or 155849 counting only the distinct ones).

The product of its (nonzero) digits is 145800, while the sum is 42.

The square root of 20569956 is about 4535.4113374643. The cubic root of 20569956 is about 273.9961460733.

The spelling of 20569956 in words is "twenty million, five hundred sixty-nine thousand, nine hundred fifty-six".