1657563640897 has 4 divisors (see below), whose sum is σ = 1673975162196. Its totient is φ = 1641152119600.

The previous prime is 1657563640879. The next prime is 1657563640963. The reversal of 1657563640897 is 7980463657561.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1087200350721 + 570363290176 = 1042689^2 + 755224^2 .

It is a cyclic number.

It is not a de Polignac number, because 1657563640897 - 2²³ = 1657555252289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1657563640807) 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, 8205760498 + ... + 8205760699.

It is an arithmetic number, because the mean of its divisors is an integer number (418493790549).

Almost surely, 2^{1657563640897} is an apocalyptic number.

It is an amenable number.

1657563640897 is a deficient number, since it is larger than the sum of its proper divisors (16411521299).

1657563640897 is a wasteful number, since it uses less digits than its factorization.

1657563640897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16411521298.

The product of its (nonzero) digits is 228614400, while the sum is 67.

The spelling of 1657563640897 in words is "one trillion, six hundred fifty-seven billion, five hundred sixty-three million, six hundred forty thousand, eight hundred ninety-seven".