7921771297 has 12 divisors (see below), whose sum is σ = 9034011504. Its totient is φ = 6888491720.

The previous prime is 7921771237. The next prime is 7921771301.

It is a happy number.

7921771297 is nontrivially palindromic in base 10.

It is a de Polignac number, because none of the positive numbers 2^k-7921771297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7921771237) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 674863 + ... + 686500.

It is an arithmetic number, because the mean of its divisors is an integer number (752834292).

Almost surely, 2^7921771297 is an apocalyptic number.

It is an amenable number.

7921771297 is a deficient number, since it is larger than the sum of its proper divisors (1112240207).

7921771297 is a wasteful number, since it uses less digits than its factorization.

7921771297 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1361420 (or 1361397 counting only the distinct ones).

The product of its digits is 777924, while the sum is 52.

The square root of 7921771297 is about 89004.3330237354. Note that the first 3 decimals coincide. The cubic root of 7921771297 is about 1993.4595761597.

The spelling of 7921771297 in words is "seven billion, nine hundred twenty-one million, seven hundred seventy-one thousand, two hundred ninety-seven".