145288021 has 2 divisors, whose sum is σ = 145288022. Its totient is φ = 145288020.

The previous prime is 145288009. The next prime is 145288037. The reversal of 145288021 is 120882541.

145288021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 142683025 + 2604996 = 11945^2 + 1614^2 .

It is a cyclic number.

It is not a de Polignac number, because 145288021 - 2¹⁹ = 144763733 is a prime.

It is a super-2 number, since 2×145288021² = 42217218092192882, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (145288061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72644010 + 72644011.

It is an arithmetic number, because the mean of its divisors is an integer number (72644011).

Almost surely, 2^145288021 is an apocalyptic number.

It is an amenable number.

145288021 is a deficient number, since it is larger than the sum of its proper divisors (1).

145288021 is an equidigital number, since it uses as much as digits as its factorization.

145288021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5120, while the sum is 31.

The square root of 145288021 is about 12053.5480668557. The cubic root of 145288021 is about 525.7064062972.

The spelling of 145288021 in words is "one hundred forty-five million, two hundred eighty-eight thousand, twenty-one".