1340823857 has 4 divisors (see below), whose sum is σ = 1344477696. Its totient is φ = 1337170020.

The previous prime is 1340823823. The next prime is 1340823877. The reversal of 1340823857 is 7583280431.

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: 7583280431 = 14969 ⋅506599.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1340823857 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1340823817) 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, 1826369 + ... + 1827102.

It is an arithmetic number, because the mean of its divisors is an integer number (336119424).

Almost surely, 2^1340823857 is an apocalyptic number.

It is an amenable number.

1340823857 is a deficient number, since it is larger than the sum of its proper divisors (3653839).

1340823857 is an equidigital number, since it uses as much as digits as its factorization.

1340823857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3653838.

The product of its (nonzero) digits is 161280, while the sum is 41.

The square root of 1340823857 is about 36617.2617354165. The cubic root of 1340823857 is about 1102.6996656425.

The spelling of 1340823857 in words is "one billion, three hundred forty million, eight hundred twenty-three thousand, eight hundred fifty-seven".