145242021 has 8 divisors (see below), whose sum is σ = 193878880. Its totient is φ = 96716592.

The previous prime is 145242001. The next prime is 145242029. The reversal of 145242021 is 120242541.

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

It is not a de Polignac number, because 145242021 - 2¹⁴ = 145225637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (145242029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24766 + ... + 30063.

It is an arithmetic number, because the mean of its divisors is an integer number (24234860).

Almost surely, 2^145242021 is an apocalyptic number.

It is an amenable number.

145242021 is a deficient number, since it is larger than the sum of its proper divisors (48636859).

145242021 is an equidigital number, since it uses as much as digits as its factorization.

145242021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55715.

The product of its (nonzero) digits is 640, while the sum is 21.

The square root of 145242021 is about 12051.6397639491. The cubic root of 145242021 is about 525.6509187052.

Adding to 145242021 its reverse (120242541), we get a palindrome (265484562).

The spelling of 145242021 in words is "one hundred forty-five million, two hundred forty-two thousand, twenty-one".