1321520145 has 32 divisors (see below), whose sum is σ = 2310405120. Its totient is φ = 639695040.

The previous prime is 1321520141. The next prime is 1321520209. The reversal of 1321520145 is 5410251231.

It is a happy number.

It is not a de Polignac number, because 1321520145 - 2² = 1321520141 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1321520141) 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 31 ways as a sum of consecutive naturals, for example, 100566 + ... + 112944.

It is an arithmetic number, because the mean of its divisors is an integer number (72200160).

Almost surely, 2^1321520145 is an apocalyptic number.

1321520145 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1321520145 is a deficient number, since it is larger than the sum of its proper divisors (988884975).

1321520145 is a wasteful number, since it uses less digits than its factorization.

1321520145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13045.

The product of its (nonzero) digits is 1200, while the sum is 24.

The square root of 1321520145 is about 36352.7185365827. The cubic root of 1321520145 is about 1097.3822449647.

Adding to 1321520145 its reverse (5410251231), we get a palindrome (6731771376).

The spelling of 1321520145 in words is "one billion, three hundred twenty-one million, five hundred twenty thousand, one hundred forty-five".