61765729 has 2 divisors, whose sum is σ = 61765730. Its totient is φ = 61765728.

The previous prime is 61765727. The next prime is 61765747. The reversal of 61765729 is 92756716.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38725729 + 23040000 = 6223^2 + 4800^2 .

It is a cyclic number.

It is not a de Polignac number, because 61765729 - 2¹ = 61765727 is a prime.

Together with 61765727, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (61765727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30882864 + 30882865.

It is an arithmetic number, because the mean of its divisors is an integer number (30882865).

Almost surely, 2^61765729 is an apocalyptic number.

It is an amenable number.

61765729 is a deficient number, since it is larger than the sum of its proper divisors (1).

61765729 is an equidigital number, since it uses as much as digits as its factorization.

61765729 is an evil number, because the sum of its binary digits is even.

The product of its digits is 158760, while the sum is 43.

The square root of 61765729 is about 7859.1175713308. The cubic root of 61765729 is about 395.2900268091.

The spelling of 61765729 in words is "sixty-one million, seven hundred sixty-five thousand, seven hundred twenty-nine".