9805645257 has 4 divisors (see below), whose sum is σ = 13074193680. Its totient is φ = 6537096836.

The previous prime is 9805645249. The next prime is 9805645273. The reversal of 9805645257 is 7525465089.

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 9805645257 - 2³ = 9805645249 is a prime.

It is a super-2 number, since 2×9805645257² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (9805645277) 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, 1634274207 + ... + 1634274212.

It is an arithmetic number, because the mean of its divisors is an integer number (3268548420).

Almost surely, 2^9805645257 is an apocalyptic number.

It is an amenable number.

9805645257 is a deficient number, since it is larger than the sum of its proper divisors (3268548423).

9805645257 is a wasteful number, since it uses less digits than its factorization.

9805645257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3268548422.

The product of its (nonzero) digits is 3024000, while the sum is 51.

The square root of 9805645257 is about 99023.4581147316. The cubic root of 9805645257 is about 2140.3857907114.

The spelling of 9805645257 in words is "nine billion, eight hundred five million, six hundred forty-five thousand, two hundred fifty-seven".