181390000 has 200 divisors, whose sum is σ = 512498448. Its totient is φ = 61440000.

The previous prime is 181389991. The next prime is 181390031. The reversal of 181390000 is 93181.

It is a tau number, because it is divible by the number of its divisors (200).

It is a Harshad number since it is a multiple of its sum of digits (22).

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1869952 + ... + 1870048.

Almost surely, 2^181390000 is an apocalyptic number.

181390000 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 181390000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (256249224).

181390000 is an abundant number, since it is smaller than the sum of its proper divisors (331108448).

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

181390000 is a wasteful number, since it uses less digits than its factorization.

181390000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153 (or 132 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 22.

The square root of 181390000 is about 13468.1104836573. The cubic root of 181390000 is about 566.0712700608.

The spelling of 181390000 in words is "one hundred eighty-one million, three hundred ninety thousand".