9961657 has 2 divisors, whose sum is σ = 9961658. Its totient is φ = 9961656.

The previous prime is 9961649. The next prime is 9961669. The reversal of 9961657 is 7561699.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9339136 + 622521 = 3056^2 + 789^2 .

It is an emirp because it is prime and its reverse (7561699) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9961657 - 2³ = 9961649 is a prime.

It is a super-2 number, since 2×9961657² = 198469220371298, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (9961607) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4980828 + 4980829.

It is an arithmetic number, because the mean of its divisors is an integer number (4980829).

Almost surely, 2^9961657 is an apocalyptic number.

It is an amenable number.

9961657 is a deficient number, since it is larger than the sum of its proper divisors (1).

9961657 is an equidigital number, since it uses as much as digits as its factorization.

9961657 is an evil number, because the sum of its binary digits is even.

The product of its digits is 102060, while the sum is 43.

The square root of 9961657 is about 3156.2092769650. The cubic root of 9961657 is about 215.1677580184.

The spelling of 9961657 in words is "nine million, nine hundred sixty-one thousand, six hundred fifty-seven".