18756820 has 12 divisors (see below), whose sum is σ = 39389364. Its totient is φ = 7502720.

The previous prime is 18756809. The next prime is 18756821. The reversal of 18756820 is 2865781.

It can be written as a sum of positive squares in 2 ways, for example, as 2208196 + 16548624 = 1486^2 + 4068^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 18756820.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18756821) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 468901 + ... + 468940.

It is an arithmetic number, because the mean of its divisors is an integer number (3282447).

Almost surely, 2^18756820 is an apocalyptic number.

18756820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18756820 is an abundant number, since it is smaller than the sum of its proper divisors (20632544).

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

18756820 is a wasteful number, since it uses less digits than its factorization.

18756820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 937850 (or 937848 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 37.

The square root of 18756820 is about 4330.9144530919. The cubic root of 18756820 is about 265.6968487531.

The spelling of 18756820 in words is "eighteen million, seven hundred fifty-six thousand, eight hundred twenty".