20865650 has 48 divisors (see below), whose sum is σ = 42747264. Its totient is φ = 7529280.

The previous prime is 20865643. The next prime is 20865653. The reversal of 20865650 is 5656802.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (20865653) 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 in 23 ways as a sum of consecutive naturals, for example, 30209 + ... + 30891.

It is an arithmetic number, because the mean of its divisors is an integer number (890568).

Almost surely, 2^20865650 is an apocalyptic number.

20865650 is an abundant number, since it is smaller than the sum of its proper divisors (21881614).

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

20865650 is a wasteful number, since it uses less digits than its factorization.

20865650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 755 (or 750 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 32.

The square root of 20865650 is about 4567.8933875475. The cubic root of 20865650 is about 275.3028069479.

The spelling of 20865650 in words is "twenty million, eight hundred sixty-five thousand, six hundred fifty".