61604065709 has 2 divisors, whose sum is σ = 61604065710. Its totient is φ = 61604065708.

The previous prime is 61604065661. The next prime is 61604065723. The reversal of 61604065709 is 90756040616.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 48864428809 + 12739636900 = 221053^2 + 112870^2 .

It is a cyclic number.

It is not a de Polignac number, because 61604065709 - 2¹² = 61604061613 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 61604065709.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61604065729) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30802032854 + 30802032855.

It is an arithmetic number, because the mean of its divisors is an integer number (30802032855).

Almost surely, 2^61604065709 is an apocalyptic number.

It is an amenable number.

61604065709 is a deficient number, since it is larger than the sum of its proper divisors (1).

61604065709 is an equidigital number, since it uses as much as digits as its factorization.

61604065709 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 272160, while the sum is 44.

The spelling of 61604065709 in words is "sixty-one billion, six hundred four million, sixty-five thousand, seven hundred nine".