7980291721 has 2 divisors, whose sum is σ = 7980291722. Its totient is φ = 7980291720.

The previous prime is 7980291703. The next prime is 7980291743. The reversal of 7980291721 is 1271920897.

7980291721 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7041727225 + 938564496 = 83915^2 + 30636^2 .

It is a cyclic number.

It is not a de Polignac number, because 7980291721 - 2¹³ = 7980283529 is a prime.

It is a super-2 number, since 2×7980291721² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (7980291751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3990145860 + 3990145861.

It is an arithmetic number, because the mean of its divisors is an integer number (3990145861).

Almost surely, 2^7980291721 is an apocalyptic number.

It is an amenable number.

7980291721 is a deficient number, since it is larger than the sum of its proper divisors (1).

7980291721 is an equidigital number, since it uses as much as digits as its factorization.

7980291721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 127008, while the sum is 46.

The square root of 7980291721 is about 89332.4785338457. The cubic root of 7980291721 is about 1998.3562929002.

The spelling of 7980291721 in words is "seven billion, nine hundred eighty million, two hundred ninety-one thousand, seven hundred twenty-one".