20170812 has 12 divisors (see below), whose sum is σ = 47065256. Its totient is φ = 6723600.

The previous prime is 20170807. The next prime is 20170831. The reversal of 20170812 is 21807102.

It is a tau number, because it is divible by the number of its divisors (12).

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, 840439 + ... + 840462.

Almost surely, 2^20170812 is an apocalyptic number.

It is an amenable number.

20170812 is an abundant number, since it is smaller than the sum of its proper divisors (26894444).

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

20170812 is a wasteful number, since it uses less digits than its factorization.

20170812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1680908 (or 1680906 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 21.

The square root of 20170812 is about 4491.1927146361. The cubic root of 20170812 is about 272.2123306014.

Adding to 20170812 its reverse (21807102), we get a palindrome (41977914).

The spelling of 20170812 in words is "twenty million, one hundred seventy thousand, eight hundred twelve".