18965550 has 48 divisors (see below), whose sum is σ = 47854080. Its totient is φ = 4969440.

The previous prime is 18965519. The next prime is 18965563. The reversal of 18965550 is 5556981.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 18965499 and 18965508.

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, 7779 + ... + 9921.

It is an arithmetic number, because the mean of its divisors is an integer number (996960).

Almost surely, 2^18965550 is an apocalyptic number.

18965550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 18965550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23927040).

18965550 is an abundant number, since it is smaller than the sum of its proper divisors (28888530).

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

18965550 is a wasteful number, since it uses less digits than its factorization.

18965550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2217 (or 2212 counting only the distinct ones).

The product of its (nonzero) digits is 54000, while the sum is 39.

The square root of 18965550 is about 4354.9454646413. The cubic root of 18965550 is about 266.6787928514.

The spelling of 18965550 in words is "eighteen million, nine hundred sixty-five thousand, five hundred fifty".