145221509 has 8 divisors (see below), whose sum is σ = 146512800. Its totient is φ = 143934736.

The previous prime is 145221481. The next prime is 145221547. The reversal of 145221509 is 905122541.

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

It is a cyclic number.

It is not a de Polignac number, because 145221509 - 2⁸ = 145221253 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 (145221709) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 101054 + ... + 102480.

It is an arithmetic number, because the mean of its divisors is an integer number (18314100).

Almost surely, 2^145221509 is an apocalyptic number.

It is an amenable number.

145221509 is a deficient number, since it is larger than the sum of its proper divisors (1291291).

145221509 is a wasteful number, since it uses less digits than its factorization.

145221509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2259.

The product of its (nonzero) digits is 3600, while the sum is 29.

The square root of 145221509 is about 12050.7887293737. The cubic root of 145221509 is about 525.6261722872.

The spelling of 145221509 in words is "one hundred forty-five million, two hundred twenty-one thousand, five hundred nine".