7860772921 has 3 divisors (see below), whose sum is σ = 7860861583. Its totient is φ = 7860684260.

The previous prime is 7860772903. The next prime is 7860772937. The reversal of 7860772921 is 1292770687.

The square root of 7860772921 is 88661.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 14356521 + 7846416400 = 3789^2 + 88580^2 .

It is not a de Polignac number, because 7860772921 - 2¹¹ = 7860770873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7860772981) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 44331 + ... + 132991.

Almost surely, 2^7860772921 is an apocalyptic number.

7860772921 is the 88661-st square number.

7860772921 is the 44331-st centered octagonal number.

It is an amenable number.

7860772921 is a deficient number, since it is larger than the sum of its proper divisors (88662).

7860772921 is an frugal number, since it uses more digits than its factorization.

7860772921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177322 (or 88661 counting only the distinct ones).

The product of its (nonzero) digits is 592704, while the sum is 49.

The cubic root of 7860772921 is about 1988.3297788369.

Multiplying 7860772921 by its sum of digits (49), we get a square (385177873129 = 620627²).

The spelling of 7860772921 in words is "seven billion, eight hundred sixty million, seven hundred seventy-two thousand, nine hundred twenty-one".