1517157397 has 4 divisors (see below), whose sum is σ = 1733894176. Its totient is φ = 1300420620.

The previous prime is 1517157379. The next prime is 1517157403. The reversal of 1517157397 is 7937517151.

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 1517157397 - 2⁷ = 1517157269 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1517157337) 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, 108368379 + ... + 108368392.

It is an arithmetic number, because the mean of its divisors is an integer number (433473544).

Almost surely, 2^1517157397 is an apocalyptic number.

It is an amenable number.

1517157397 is a deficient number, since it is larger than the sum of its proper divisors (216736779).

1517157397 is an equidigital number, since it uses as much as digits as its factorization.

1517157397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216736778.

The product of its digits is 231525, while the sum is 46.

The square root of 1517157397 is about 38950.7047047932. The cubic root of 1517157397 is about 1149.0622214988.

The spelling of 1517157397 in words is "one billion, five hundred seventeen million, one hundred fifty-seven thousand, three hundred ninety-seven".