145481931 has 18 divisors (see below), whose sum is σ = 244449972. Its totient is φ = 83132280.

The previous prime is 145481927. The next prime is 145481957. The reversal of 145481931 is 139184541.

145481931 is a `hidden beast` number, since 145 + 481 + 9 + 31 = 666.

145481931 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 145481931 - 2² = 145481927 is a prime.

It is a super-2 number, since 2×145481931² = 42329984494977522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (145481731) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 164505 + ... + 165386.

It is an arithmetic number, because the mean of its divisors is an integer number (13580554).

Almost surely, 2^145481931 is an apocalyptic number.

145481931 is a deficient number, since it is larger than the sum of its proper divisors (98968041).

145481931 is a wasteful number, since it uses less digits than its factorization.

145481931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 329911 (or 329901 counting only the distinct ones).

The product of its digits is 17280, while the sum is 36.

The square root of 145481931 is about 12061.5890744130. The cubic root of 145481931 is about 525.9401819623.

The spelling of 145481931 in words is "one hundred forty-five million, four hundred eighty-one thousand, nine hundred thirty-one".