145542021 has 4 divisors (see below), whose sum is σ = 194056032. Its totient is φ = 97028012.

The previous prime is 145542017. The next prime is 145542029. The reversal of 145542021 is 120245541.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 145542021 - 2² = 145542017 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 145541982 and 145542000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (145542029) 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 3 ways as a sum of consecutive naturals, for example, 24257001 + ... + 24257006.

It is an arithmetic number, because the mean of its divisors is an integer number (48514008).

Almost surely, 2^145542021 is an apocalyptic number.

It is an amenable number.

145542021 is a deficient number, since it is larger than the sum of its proper divisors (48514011).

145542021 is an equidigital number, since it uses as much as digits as its factorization.

145542021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48514010.

The product of its (nonzero) digits is 1600, while the sum is 24.

The square root of 145542021 is about 12064.0797825611. The cubic root of 145542021 is about 526.0125836118.

Adding to 145542021 its reverse (120245541), we get a palindrome (265787562).

The spelling of 145542021 in words is "one hundred forty-five million, five hundred forty-two thousand, twenty-one".