1340523557 has 4 divisors (see below), whose sum is σ = 1340867136. Its totient is φ = 1340179980.

The previous prime is 1340523553. The next prime is 1340523563. The reversal of 1340523557 is 7553250431.

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: 7553250431 = 6203 ⋅1217677.

It is a cyclic number.

It is not a de Polignac number, because 1340523557 - 2² = 1340523553 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 (1340523553) 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, 165869 + ... + 173762.

It is an arithmetic number, because the mean of its divisors is an integer number (335216784).

Almost surely, 2^1340523557 is an apocalyptic number.

It is an amenable number.

1340523557 is a deficient number, since it is larger than the sum of its proper divisors (343579).

1340523557 is an equidigital number, since it uses as much as digits as its factorization.

1340523557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 343578.

The product of its (nonzero) digits is 63000, while the sum is 35.

The square root of 1340523557 is about 36613.1609807184. The cubic root of 1340523557 is about 1102.6173367985.

Adding to 1340523557 its reverse (7553250431), we get a palindrome (8893773988).

The spelling of 1340523557 in words is "one billion, three hundred forty million, five hundred twenty-three thousand, five hundred fifty-seven".