1005145221 has 4 divisors (see below), whose sum is σ = 1340193632. Its totient is φ = 670096812.

The previous prime is 1005145187. The next prime is 1005145223. The reversal of 1005145221 is 1225415001.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1225415001 = 3 ⋅408471667.

It is not a de Polignac number, because 1005145221 - 2⁶ = 1005145157 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 (1005145223) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 167524201 + ... + 167524206.

It is an arithmetic number, because the mean of its divisors is an integer number (335048408).

Almost surely, 2^1005145221 is an apocalyptic number.

It is an amenable number.

1005145221 is a deficient number, since it is larger than the sum of its proper divisors (335048411).

1005145221 is an equidigital number, since it uses as much as digits as its factorization.

1005145221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 335048410.

The product of its (nonzero) digits is 400, while the sum is 21.

The square root of 1005145221 is about 31704.0253122533. The cubic root of 1005145221 is about 1001.7121405683.

The spelling of 1005145221 in words is "one billion, five million, one hundred forty-five thousand, two hundred twenty-one".