9791228137 has 2 divisors, whose sum is σ = 9791228138. Its totient is φ = 9791228136.

The previous prime is 9791228131. The next prime is 9791228171. The reversal of 9791228137 is 7318221979.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9411134121 + 380094016 = 97011^2 + 19496^2 .

It is a cyclic number.

It is not a de Polignac number, because 9791228137 - 2¹⁵ = 9791195369 is a prime.

It is not a weakly prime, because it can be changed into another prime (9791228131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4895614068 + 4895614069.

It is an arithmetic number, because the mean of its divisors is an integer number (4895614069).

Almost surely, 2^9791228137 is an apocalyptic number.

It is an amenable number.

9791228137 is a deficient number, since it is larger than the sum of its proper divisors (1).

9791228137 is an equidigital number, since it uses as much as digits as its factorization.

9791228137 is an evil number, because the sum of its binary digits is even.

The product of its digits is 381024, while the sum is 49.

The square root of 9791228137 is about 98950.6348488983. The cubic root of 9791228137 is about 2139.3362818545.

The spelling of 9791228137 in words is "nine billion, seven hundred ninety-one million, two hundred twenty-eight thousand, one hundred thirty-seven".