9139771921 has 16 divisors (see below), whose sum is σ = 10808864640. Its totient is φ = 7561693440.

The previous prime is 9139771909. The next prime is 9139771939. The reversal of 9139771921 is 1291779319.

It is not a de Polignac number, because 9139771921 - 2⁷ = 9139771793 is a prime.

It is not an unprimeable number, because it can be changed into a prime (9139771961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1312170 + ... + 1319116.

It is an arithmetic number, because the mean of its divisors is an integer number (675554040).

Almost surely, 2^9139771921 is an apocalyptic number.

It is an amenable number.

9139771921 is a deficient number, since it is larger than the sum of its proper divisors (1669092719).

9139771921 is a wasteful number, since it uses less digits than its factorization.

9139771921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13464.

The product of its digits is 214326, while the sum is 49.

The square root of 9139771921 is about 95602.1543742608. The cubic root of 9139771921 is about 2090.7966042969.

The spelling of 9139771921 in words is "nine billion, one hundred thirty-nine million, seven hundred seventy-one thousand, nine hundred twenty-one".