188493390 has 48 divisors (see below), whose sum is σ = 490872096. Its totient is φ = 50184000.

The previous prime is 188493353. The next prime is 188493391. The reversal of 188493390 is 93394881.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (188493391) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 72615 + ... + 75165.

It is an arithmetic number, because the mean of its divisors is an integer number (10226502).

Almost surely, 2^188493390 is an apocalyptic number.

188493390 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

188493390 is an abundant number, since it is smaller than the sum of its proper divisors (302378706).

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

188493390 is a wasteful number, since it uses less digits than its factorization.

188493390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3385 (or 3382 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The square root of 188493390 is about 13729.2894936337. The cubic root of 188493390 is about 573.3661393553.

The spelling of 188493390 in words is "one hundred eighty-eight million, four hundred ninety-three thousand, three hundred ninety".