6720399869 has 2 divisors, whose sum is σ = 6720399870. Its totient is φ = 6720399868.

The previous prime is 6720399853. The next prime is 6720399901. The reversal of 6720399869 is 9689930276.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6514104100 + 206295769 = 80710^2 + 14363^2 .

It is a cyclic number.

It is not a de Polignac number, because 6720399869 - 2⁴ = 6720399853 is a prime.

It is a super-2 number, since 2×6720399869² = 90327548798510434322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6720399839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3360199934 + 3360199935.

It is an arithmetic number, because the mean of its divisors is an integer number (3360199935).

Almost surely, 2^6720399869 is an apocalyptic number.

It is an amenable number.

6720399869 is a deficient number, since it is larger than the sum of its proper divisors (1).

6720399869 is an equidigital number, since it uses as much as digits as its factorization.

6720399869 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8817984, while the sum is 59.

The square root of 6720399869 is about 81978.0450425600. The cubic root of 6720399869 is about 1887.1150211377.

The spelling of 6720399869 in words is "six billion, seven hundred twenty million, three hundred ninety-nine thousand, eight hundred sixty-nine".