188145405 has 48 divisors (see below), whose sum is σ = 388926720. Its totient is φ = 82266624.

The previous prime is 188145401. The next prime is 188145413. The reversal of 188145405 is 504541881.

It is not a de Polignac number, because 188145405 - 2² = 188145401 is a prime.

It is a super-2 number, since 2×188145405² = 70797386845228050, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 188145405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (188145401) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5740 + ... + 20229.

It is an arithmetic number, because the mean of its divisors is an integer number (8102640).

Almost surely, 2^188145405 is an apocalyptic number.

188145405 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

188145405 is an abundant number, since it is smaller than the sum of its proper divisors (200781315).

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

188145405 is a wasteful number, since it uses less digits than its factorization.

188145405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26010 (or 26007 counting only the distinct ones).

The product of its (nonzero) digits is 25600, while the sum is 36.

The square root of 188145405 is about 13716.6105507155. The cubic root of 188145405 is about 573.0130841379.

The spelling of 188145405 in words is "one hundred eighty-eight million, one hundred forty-five thousand, four hundred five".