1321520149 has 4 divisors (see below), whose sum is σ = 1336368780. Its totient is φ = 1306671520.

The previous prime is 1321520141. The next prime is 1321520209. The reversal of 1321520149 is 9410251231.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 869660100 + 451860049 = 29490^2 + 21257^2 .

It is a cyclic number.

It is not a de Polignac number, because 1321520149 - 2³ = 1321520141 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 (1321520141) 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, 7424182 + ... + 7424359.

It is an arithmetic number, because the mean of its divisors is an integer number (334092195).

Almost surely, 2^1321520149 is an apocalyptic number.

It is an amenable number.

1321520149 is a deficient number, since it is larger than the sum of its proper divisors (14848631).

1321520149 is an equidigital number, since it uses as much as digits as its factorization.

1321520149 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14848630.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 1321520149 is about 36352.7185915992. The cubic root of 1321520149 is about 1097.3822460719.

The spelling of 1321520149 in words is "one billion, three hundred twenty-one million, five hundred twenty thousand, one hundred forty-nine".