61720663 has 2 divisors, whose sum is σ = 61720664. Its totient is φ = 61720662.

The previous prime is 61720657. The next prime is 61720669. The reversal of 61720663 is 36602716.

It is a balanced prime because it is at equal distance from previous prime (61720657) and next prime (61720669).

It is a cyclic number.

It is not a de Polignac number, because 61720663 - 2¹³ = 61712471 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61720669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30860331 + 30860332.

It is an arithmetic number, because the mean of its divisors is an integer number (30860332).

Almost surely, 2^61720663 is an apocalyptic number.

61720663 is a deficient number, since it is larger than the sum of its proper divisors (1).

61720663 is an equidigital number, since it uses as much as digits as its factorization.

61720663 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9072, while the sum is 31.

The square root of 61720663 is about 7856.2499323787. The cubic root of 61720663 is about 395.1938652054.

The spelling of 61720663 in words is "sixty-one million, seven hundred twenty thousand, six hundred sixty-three".