7420721117 has 2 divisors, whose sum is σ = 7420721118. Its totient is φ = 7420721116.

The previous prime is 7420721089. The next prime is 7420721123. The reversal of 7420721117 is 7111270247.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5750037241 + 1670683876 = 75829^2 + 40874^2 .

It is a cyclic number.

It is not a de Polignac number, because 7420721117 - 2⁸ = 7420720861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7420721167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3710360558 + 3710360559.

It is an arithmetic number, because the mean of its divisors is an integer number (3710360559).

Almost surely, 2^7420721117 is an apocalyptic number.

It is an amenable number.

7420721117 is a deficient number, since it is larger than the sum of its proper divisors (1).

7420721117 is an equidigital number, since it uses as much as digits as its factorization.

7420721117 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5488, while the sum is 32.

The square root of 7420721117 is about 86143.6075225550. The cubic root of 7420721117 is about 1950.5123454966.

The spelling of 7420721117 in words is "seven billion, four hundred twenty million, seven hundred twenty-one thousand, one hundred seventeen".