1305949981 has 4 divisors (see below), whose sum is σ = 1492514272. Its totient is φ = 1119385692.

The previous prime is 1305949951. The next prime is 1305949987. The reversal of 1305949981 is 1899495031.

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 1305949981 - 2⁵ = 1305949949 is a prime.

It is a super-2 number, since 2×1305949981² = 3411010705747800722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1305949987) 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, 93282135 + ... + 93282148.

It is an arithmetic number, because the mean of its divisors is an integer number (373128568).

Almost surely, 2^1305949981 is an apocalyptic number.

It is an amenable number.

1305949981 is a deficient number, since it is larger than the sum of its proper divisors (186564291).

1305949981 is an equidigital number, since it uses as much as digits as its factorization.

1305949981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186564290.

The product of its (nonzero) digits is 349920, while the sum is 49.

The square root of 1305949981 is about 36137.9299490162. The cubic root of 1305949981 is about 1093.0554176526.

The spelling of 1305949981 in words is "one billion, three hundred five million, nine hundred forty-nine thousand, nine hundred eighty-one".