1331653261 has 4 divisors (see below), whose sum is σ = 1335282112. Its totient is φ = 1328024412.

The previous prime is 1331653259. The next prime is 1331653313. The reversal of 1331653261 is 1623561331.

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.

It is a cyclic number.

It is not a de Polignac number, because 1331653261 - 2¹ = 1331653259 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 (1331653201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1813875 + ... + 1814608.

It is an arithmetic number, because the mean of its divisors is an integer number (333820528).

Almost surely, 2^1331653261 is an apocalyptic number.

It is an amenable number.

1331653261 is a deficient number, since it is larger than the sum of its proper divisors (3628851).

1331653261 is an equidigital number, since it uses as much as digits as its factorization.

1331653261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3628850.

The product of its digits is 9720, while the sum is 31.

The square root of 1331653261 is about 36491.8245775681. The cubic root of 1331653261 is about 1100.1799322740.

The spelling of 1331653261 in words is "one billion, three hundred thirty-one million, six hundred fifty-three thousand, two hundred sixty-one".