20805016 has 8 divisors (see below), whose sum is σ = 39009420. Its totient is φ = 10402504.

The previous prime is 20805011. The next prime is 20805017. The reversal of 20805016 is 61050802.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20805011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1300306 + ... + 1300321.

Almost surely, 2^20805016 is an apocalyptic number.

It is an amenable number.

20805016 is a deficient number, since it is larger than the sum of its proper divisors (18204404).

20805016 is a wasteful number, since it uses less digits than its factorization.

20805016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2600633 (or 2600629 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 20805016 is about 4561.2515826251. The cubic root of 20805016 is about 275.0358785144.

Adding to 20805016 its reverse (61050802), we get a palindrome (81855818).

The spelling of 20805016 in words is "twenty million, eight hundred five thousand, sixteen".