1305509497 has 4 divisors (see below), whose sum is σ = 1306949776. Its totient is φ = 1304069220.

The previous prime is 1305509477. The next prime is 1305509507. The reversal of 1305509497 is 7949055031.

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 1305509497 - 2²⁷ = 1171291769 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1305509467) 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, 718779 + ... + 720592.

It is an arithmetic number, because the mean of its divisors is an integer number (326737444).

Almost surely, 2^1305509497 is an apocalyptic number.

It is an amenable number.

1305509497 is a deficient number, since it is larger than the sum of its proper divisors (1440279).

1305509497 is an equidigital number, since it uses as much as digits as its factorization.

1305509497 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1440278.

The product of its (nonzero) digits is 170100, while the sum is 43.

The square root of 1305509497 is about 36131.8349520198. The cubic root of 1305509497 is about 1092.9325115761.

The spelling of 1305509497 in words is "one billion, three hundred five million, five hundred nine thousand, four hundred ninety-seven".