61720369 has 2 divisors, whose sum is σ = 61720370. Its totient is φ = 61720368.

The previous prime is 61720363. The next prime is 61720397. The reversal of 61720369 is 96302716.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 57153600 + 4566769 = 7560^2 + 2137^2 .

It is a cyclic number.

It is not a de Polignac number, because 61720369 - 2¹³ = 61712177 is a prime.

It is a super-2 number, since 2×61720369² = 7618807898992322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (61720363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30860184 + 30860185.

It is an arithmetic number, because the mean of its divisors is an integer number (30860185).

Almost surely, 2^61720369 is an apocalyptic number.

It is an amenable number.

61720369 is a deficient number, since it is larger than the sum of its proper divisors (1).

61720369 is an equidigital number, since it uses as much as digits as its factorization.

61720369 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13608, while the sum is 34.

The square root of 61720369 is about 7856.2312211391. The cubic root of 61720369 is about 395.1932377160.

The spelling of 61720369 in words is "sixty-one million, seven hundred twenty thousand, three hundred sixty-nine".