20180916 has 72 divisors (see below), whose sum is σ = 59439744. Its totient is φ = 5653440.

The previous prime is 20180879. The next prime is 20180933. The reversal of 20180916 is 61908102.

It is a self number, because there is not a number n which added to its sum of digits gives 20180916.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12601 + ... + 14111.

It is an arithmetic number, because the mean of its divisors is an integer number (825552).

Almost surely, 2^20180916 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20180916, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29719872).

20180916 is an abundant number, since it is smaller than the sum of its proper divisors (39258828).

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

20180916 is a wasteful number, since it uses less digits than its factorization.

20180916 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1581 (or 1576 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 20180916 is about 4492.3174420337. The cubic root of 20180916 is about 272.2577753802.

The spelling of 20180916 in words is "twenty million, one hundred eighty thousand, nine hundred sixteen".