18961020 has 192 divisors, whose sum is σ = 66138240. Its totient is φ = 4478976.

The previous prime is 18961009. The next prime is 18961043. The reversal of 18961020 is 2016981.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 259704 + ... + 259776.

It is an arithmetic number, because the mean of its divisors is an integer number (344470).

Almost surely, 2^18961020 is an apocalyptic number.

18961020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18961020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33069120).

18961020 is an abundant number, since it is smaller than the sum of its proper divisors (47177220).

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

18961020 is a wasteful number, since it uses less digits than its factorization.

18961020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141 (or 133 counting only the distinct ones).

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

The square root of 18961020 is about 4354.4253352193. The cubic root of 18961020 is about 266.6575587167.

It can be divided in two parts, 1896 and 1020, that added together give a square (2916 = 54²).

The spelling of 18961020 in words is "eighteen million, nine hundred sixty-one thousand, twenty".