9987428307257 has 8 divisors (see below), whose sum is σ = 10424607547200. Its totient is φ = 9550494336240.

The previous prime is 9987428307251. The next prime is 9987428307271. The reversal of 9987428307257 is 7527038247899.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 9987428307257 - 2⁸ = 9987428307001 is a prime.

It is not an unprimeable number, because it can be changed into a prime (9987428307251) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 61234007 + ... + 61396892.

It is an arithmetic number, because the mean of its divisors is an integer number (1303075943400).

Almost surely, 2^{9987428307257} is an apocalyptic number.

It is an amenable number.

9987428307257 is a deficient number, since it is larger than the sum of its proper divisors (437179239943).

9987428307257 is a wasteful number, since it uses less digits than its factorization.

9987428307257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122634463.

The product of its (nonzero) digits is 426746880, while the sum is 71.

The spelling of 9987428307257 in words is "nine trillion, nine hundred eighty-seven billion, four hundred twenty-eight million, three hundred seven thousand, two hundred fifty-seven".