145681890 has 16 divisors (see below), whose sum is σ = 349636608. Its totient is φ = 38848496.

The previous prime is 145681889. The next prime is 145681933. The reversal of 145681890 is 98186541.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2428002 + ... + 2428061.

It is an arithmetic number, because the mean of its divisors is an integer number (21852288).

Almost surely, 2^145681890 is an apocalyptic number.

145681890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

145681890 is an abundant number, since it is smaller than the sum of its proper divisors (203954718).

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

145681890 is a wasteful number, since it uses less digits than its factorization.

145681890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4856073.

The product of its (nonzero) digits is 69120, while the sum is 42.

The square root of 145681890 is about 12069.8753100436. The cubic root of 145681890 is about 526.1810327826.

The spelling of 145681890 in words is "one hundred forty-five million, six hundred eighty-one thousand, eight hundred ninety".