1021245145 has 4 divisors (see below), whose sum is σ = 1225494180. Its totient is φ = 816996112.

The previous prime is 1021245143. The next prime is 1021245151. The reversal of 1021245145 is 5415421201.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5415421201 = 1667 ⋅3248603.

It can be written as a sum of positive squares in 2 ways, for example, as 636653824 + 384591321 = 25232^2 + 19611^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021245145 - 2¹ = 1021245143 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1021245143) 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, 102124510 + ... + 102124519.

It is an arithmetic number, because the mean of its divisors is an integer number (306373545).

Almost surely, 2^1021245145 is an apocalyptic number.

It is an amenable number.

1021245145 is a deficient number, since it is larger than the sum of its proper divisors (204249035).

1021245145 is an equidigital number, since it uses as much as digits as its factorization.

1021245145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204249034.

The product of its (nonzero) digits is 1600, while the sum is 25.

The square root of 1021245145 is about 31956.9264010167. The cubic root of 1021245145 is about 1007.0321479790.

Adding to 1021245145 its reverse (5415421201), we get a palindrome (6436666346).

The spelling of 1021245145 in words is "one billion, twenty-one million, two hundred forty-five thousand, one hundred forty-five".