7656457621 has 2 divisors, whose sum is σ = 7656457622. Its totient is φ = 7656457620.

The previous prime is 7656457609. The next prime is 7656457657. The reversal of 7656457621 is 1267546567.

7656457621 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., 7619369521 + 37088100 = 87289^2 + 6090^2 .

It is a cyclic number.

It is not a de Polignac number, because 7656457621 - 2²⁹ = 7119586709 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7656452621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3828228810 + 3828228811.

It is an arithmetic number, because the mean of its divisors is an integer number (3828228811).

Almost surely, 2^7656457621 is an apocalyptic number.

It is an amenable number.

7656457621 is a deficient number, since it is larger than the sum of its proper divisors (1).

7656457621 is an equidigital number, since it uses as much as digits as its factorization.

7656457621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2116800, while the sum is 49.

The square root of 7656457621 is about 87501.1863976712. The cubic root of 7656457621 is about 1970.9516064409.

The spelling of 7656457621 in words is "seven billion, six hundred fifty-six million, four hundred fifty-seven thousand, six hundred twenty-one".