145293981 has 8 divisors (see below), whose sum is σ = 221400384. Its totient is φ = 83025120.

The previous prime is 145293977. The next prime is 145293991. The reversal of 145293981 is 189392541.

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

It is not a de Polignac number, because 145293981 - 2² = 145293977 is a prime.

It is a super-2 number, since 2×145293981² = 42220681829656722, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (145293961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3459360 + ... + 3459401.

It is an arithmetic number, because the mean of its divisors is an integer number (27675048).

Almost surely, 2^145293981 is an apocalyptic number.

It is an amenable number.

145293981 is a deficient number, since it is larger than the sum of its proper divisors (76106403).

145293981 is an equidigital number, since it uses as much as digits as its factorization.

145293981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6918771.

The product of its digits is 77760, while the sum is 42.

The square root of 145293981 is about 12053.7952944291. The cubic root of 145293981 is about 525.7135947020.

The spelling of 145293981 in words is "one hundred forty-five million, two hundred ninety-three thousand, nine hundred eighty-one".