1720661153 has 2 divisors, whose sum is σ = 1720661154. Its totient is φ = 1720661152.

The previous prime is 1720661143. The next prime is 1720661167. The reversal of 1720661153 is 3511660271.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1598160529 + 122500624 = 39977^2 + 11068^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1720661153 is a prime.

It is not a weakly prime, because it can be changed into another prime (1720661143) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 860330576 + 860330577.

It is an arithmetic number, because the mean of its divisors is an integer number (860330577).

Almost surely, 2^1720661153 is an apocalyptic number.

It is an amenable number.

1720661153 is a deficient number, since it is larger than the sum of its proper divisors (1).

1720661153 is an equidigital number, since it uses as much as digits as its factorization.

1720661153 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7560, while the sum is 32.

The square root of 1720661153 is about 41480.8528480310. The cubic root of 1720661153 is about 1198.2987821787.

The spelling of 1720661153 in words is "one billion, seven hundred twenty million, six hundred sixty-one thousand, one hundred fifty-three".