1309856497 has 4 divisors (see below), whose sum is σ = 1340318320. Its totient is φ = 1279394676.

The previous prime is 1309856437. The next prime is 1309856519. The reversal of 1309856497 is 7946589031.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 7946589031 = 7193 ⋅1104767.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1309856497 is a prime.

It is a super-2 number, since 2×1309856497² = 3431448085466222018, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1309856437) 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, 15230847 + ... + 15230932.

It is an arithmetic number, because the mean of its divisors is an integer number (335079580).

Almost surely, 2^1309856497 is an apocalyptic number.

It is an amenable number.

1309856497 is a deficient number, since it is larger than the sum of its proper divisors (30461823).

1309856497 is an equidigital number, since it uses as much as digits as its factorization.

1309856497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30461822.

The product of its (nonzero) digits is 1632960, while the sum is 52.

The square root of 1309856497 is about 36191.9396689373. The cubic root of 1309856497 is about 1094.1442260337.

The spelling of 1309856497 in words is "one billion, three hundred nine million, eight hundred fifty-six thousand, four hundred ninety-seven".