145681931 has 8 divisors (see below), whose sum is σ = 153026304. Its totient is φ = 138421800.

The previous prime is 145681889. The next prime is 145681933. The reversal of 145681931 is 139186541.

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

It is a cyclic number.

It is not a de Polignac number, because 145681931 - 2⁶ = 145681867 is a prime.

It is a super-2 number, since 2×145681931² = 42446450039777522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (145681933) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17501 + ... + 24446.

It is an arithmetic number, because the mean of its divisors is an integer number (19128288).

Almost surely, 2^145681931 is an apocalyptic number.

145681931 is a deficient number, since it is larger than the sum of its proper divisors (7344373).

145681931 is a wasteful number, since it uses less digits than its factorization.

145681931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42121.

The product of its digits is 25920, while the sum is 38.

The square root of 145681931 is about 12069.8770084869. The cubic root of 145681931 is about 526.1810821445.

The spelling of 145681931 in words is "one hundred forty-five million, six hundred eighty-one thousand, nine hundred thirty-one".