190821138 has 8 divisors (see below), whose sum is σ = 381642288. Its totient is φ = 63607044.

The previous prime is 190821119. The next prime is 190821139. The reversal of 190821138 is 831128091.

It is a sphenic number, since it is the product of 3 distinct primes.

190821138 is an admirable number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 190821099 and 190821108.

It is not an unprimeable number, because it can be changed into a prime (190821139) 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, 15901756 + ... + 15901767.

It is an arithmetic number, because the mean of its divisors is an integer number (47705286).

Almost surely, 2^190821138 is an apocalyptic number.

190821138 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

190821138 is a wasteful number, since it uses less digits than its factorization.

190821138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31803528.

The product of its (nonzero) digits is 3456, while the sum is 33.

The square root of 190821138 is about 13813.8024453805. The cubic root of 190821138 is about 575.7166997564.

The spelling of 190821138 in words is "one hundred ninety million, eight hundred twenty-one thousand, one hundred thirty-eight".